| 1 Preface | 1
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| 1.1 Scope | 1
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| What this book is | 1
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| What this book is not | 1
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| Intended audience | 1
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| Orientation | 1
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| 1.2 The most important point | 2
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| 1.3 About | 2
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| About me | 2
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| About my company | 3
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| About this book | 3
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| |
| About the contributors | 3
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| 2 Fundamental concepts | 5
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| 2.1 Introduction | 5
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| 2.2 Terminology and misnomers | 5
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| 2.2.1 Cell vs battery | 5
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| 2.2.2 Anode and cathode | 6
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| 2.2.3 Lithium vs Li-ion | 7
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| 2.2.4 "LiPo" | 7
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| 2.2.5 Li-ion vs LiFePO4 or other chemistry | 7
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| 2.2.6 "C-rating" | 7
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| 2.3 Common misunderstandings | 8
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| 2.3.1 Charging while discharging | 8
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| 2.3.2 AC adapter current too high | 9
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| 2.3.3 Over-unity | 9
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| 2.3.4 Confused measures | 10
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| 2.4 Measures | 10
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| 2.4.1 Ω - Resistance and impedance | 10
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| 2.4.2 V - Voltage | 11
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| 2.4.3 Ah - Charge, capacity | 11
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| Charge | 12
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| Capacity | 12
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| Effective capacity | 12
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| Other measures | 12
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| 2.4.4 % - Charge efficiency | 12
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| 2.4.5 A - Current | 12
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| Sign | 13
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| 2.4.6 1/h - Specific current, "C-rate" | 13
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| 2.4.7 Wh, J - Energy | 13
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| 2.4.8 Wh/kg, J/kg - Specific energy | 14
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| 2.4.9 Wh/l, J/l - Energy density | 14
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| 2.4.10 % - Energy efficiency | 14
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| 2.4.11 W - Power | 15
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| 2.4.12 W/kg - Specific power | 15
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| 2.4.13 W/l - Power density | 15
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| 2.4.14 % - Power efficiency | 15
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| 2.4.15 F - Capacitance | 16
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| 2.5 Maximum Power Point | 16
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| 2.6 Maximum Power Time | 17
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| 2.6.1 MPT definition | 18
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| 2.6.2 MPT empirical characterization | 18
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| Timing a discharge cycle | 18
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| From voltage sag | 18
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| 2.6.3 MPT derivation from specs | 19
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| From specification data | 19
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| From discharge curves | 19
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| 2.6.4 Typical values of MPT | 20
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| 2.6.5 MPT conversions | 21
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| Series resistance calculation | 21
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| Energy efficiency calculation | 22
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| Voltage sag calculation | 23
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| 2.6.6 Using the MPT | 23
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| 2.7 States | 24
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| 2.7.1 States of alphabet soup | 24
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| 2.7.2 State of Charge (SoC) | 25
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| Physical SoC | 25
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| Operating SoC | 25
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| String SoC | 26
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| Array SoC | 26
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| 2.7.3 State of Energy (SoE) | 26
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| 2.7.4 State of Health (SoH) | 27
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| 2.7.5 Other "State of" | 27
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| 2.7.6 Depth of Discharge (DoD) | 28
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| 2.7.7 Charge Acceptance, Discharge Availability | 28
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| 2.8 Charts | 29
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| 2.8.1 Radar chart | 30
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| 2.8.2 Ragone plot | 32
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| 2.8.3 MPT based Ragone plot | 37
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| 2.9 Power conversion | 39
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| 2.9.1 AC to DC | 40
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| 2.9.2 DC to DC | 41
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| Charger with DC input | 42
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| 2.9.3 DC to AC | 42
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| Inverter | 42
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| 2.9.4 Bidirectional AC and DC | 42
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| Inverger (charger / inverter, "combi") | 42
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| AC motor driver for traction | 42
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| 2.9.5 Any direction | 43
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| Transverter | 43
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| 2.10 Electrical schematic diagram symbols | 43
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| 3 Li-ion cells | 45
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| 3.1 Introduction | 45
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| 3.1.1 Cell definition | 45
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| 3.2 Types of cells | 45
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| 3.2.1 Cell chemistry | 46
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| 3.2.2 Cell formats | 48
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| Small cylindrical | 49
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| Large cylindrical | 49
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| Large prismatic | 49
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| Small prismatic | 50
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| Pouch | 50
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| 3.2.3 Energy vs power cells | 50
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| 3.3 Cell characterization | 52
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| 3.3.1 Perspectives for characterization | 52
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| 3.3.2 Equivalent model | 52
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| 3.3.3 Safe Operating Area (SOA) | 53
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| Safety | 55
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| 3.3.4 Cell life | 55
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| Cycle and calendar life | 55
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| Cycle life | 56
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| Calendar life | 56
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| 3.4 Voltage and SoC | 56
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| 3.4.1 Terminal voltage and Open Circuit Voltage (OCV) | 57
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| IR drop, voltage sag | 57
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| Relaxation | 58
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| Hysteresis | 58
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| 3.4.2 Voltage ranges | 59
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| 3.4.3 Voltage vs SoC curves | 60
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| Discharge curves | 60
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| CCCV charging curves | 61
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| OCV vs SoC curve | 63
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| Differential OCV vs SoC | 64
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| 3.4.4 Cell SoC | 65
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| 3.4.5 Voltage specifications and characteristics | 66
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| Spec sheet | 66
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| OCV vs SoC table | 66
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| 3.4.6 Expansion and contraction | 67
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| Allowing for expansion | 68
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| 3.5 Capacity, energy, and charge efficiency | 68
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| 3.5.1 Capacity | 68
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| Nominal capacity | 68
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| Operational capacity | 68
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| Effective capacity | 69
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| 3.5.2 Capacity fade, cycle life | 69
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| Minimizing capacity fade, maximizing cell use | 70
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| Cycle life prolongation | 74
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| 3.5.3 Capacity fade, calendar life | 74
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| 3.5.4 Energy | 74
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| Energy density and specific energy | 75
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| Operational and effective energy | 75
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| Actual Energy | 76
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| 3.5.5 Energy efficiency | 76
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| 3.5.6 Charge efficiency | 76
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| Life | 77
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| 3.6 Resistance, impedance, maximum power time | 77
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| 3.6.1 Resistance and Maximum Power Time | 77
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| Nominal DC resistance | 77
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| Actual DC resistance | 77
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| Resistance degradation | 78
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| Nominal MPT | 79
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| 3.6.2 Impedance | 82
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| 3.7 Current, power and self-discharge | 83
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| 3.7.1 Current | 83
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| Typical characteristics | 83
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| Specifications | 83
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| Maximum power current | 84
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| Operational current limits | 84
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| 3.7.2 Power | 84
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| 3.7.3 Self-discharge current | 85
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| 3.8 Cell selection and procurement | 88
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| 3.8.1 Liars, damn liars, and battery manufacturers | 88
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| 3.8.2 Reading specification sheets | 88
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| Verification | 88
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| Spec sheets styles | 88
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| Cell part number | 89
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| Voltage | 89
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| Capacity | 90
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| Charging limits | 90
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| Discharging limits | 91
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| Energy | 91
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| Power | 91
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| Energy density and specific energy | 92
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| Power density and specific power | 92
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| Temperature | 92
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| AC Impedance | 92
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| DC Resistance | 92
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| Cycle Life | 92
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| Calendar life | 93
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| Mass (weight) | 93
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| Size | 93
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| Curves | 93
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| Power curves | 96
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| 3.8.3 Cell sourcing | 97
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| 4 Cell arrangement | 99
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| 4.1 Introduction | 99
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| 4.1.1 Possible cell arrangements | 99
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| 4.1.2 Cell arrangement notation | 99
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| 4.1.3 Cell arrangement characteristics | 101
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| Parallel and series connection | 101
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| 4.1.4 Module arrangement | 102
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| 4.2 Series strings | 103
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| 4.2.1 Current in series strings | 103
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| Charging and discharging | 103
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| Stopping charging and discharging | 105
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| Main fuse | 105
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| Safety disconnect | 105
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| 4.2.2 Voltage in series strings | 106
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| Maximum string voltage | 106
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| 4.2.3 Mismatched cells in series strings | 107
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| 4.2.4 String SoC | 107
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| 4.2.5 String imbalance | 108
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| Balanced vs imbalanced | 108
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| Same capacity, balanced | 109
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| Same capacity, unbalanced | 110
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| Different capacity, mid balanced | 112
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| State of Balance | 113
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| 4.2.6 Optimal balance point | 113
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| 4.2.7 Imbalance detection | 115
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| 4.2.8 Imbalance causes | 116
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| Self discharge | 117
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| Cycling | 117
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| 4.2.9 Balancing | 118
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| Required balancing current | 118
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| Balancing methods | 118
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| Balancing time | 119
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| 4.2.10 Over-discharge and reversal | 119
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| 4.2.11 Transitional spikes | 120
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| Negative spikes | 120
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| Positive spikes | 121
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| 4.3 Parallel blocks | 122
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| 4.3.1 Voltage in parallel blocks | 122
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| 4.3.2 Current in parallel blocks | 122
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| 4.3.3 Temperature in parallel blocks | 123
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| 4.3.4 Mismatched cells in parallel blocks | 123
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| 4.3.5 Fuse-per-cell | 123
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| Individual fuses are required | 124
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| Individual fuses create more problems than they solve | 124
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| Individual fuses are a solution in search of a problem | 125
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| 4.3.6 Many small cells in parallel vs one large cell | 127
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| 4.3.7 Equalizing inrush current | 127
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| 4.4 Parallel-first | 132
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| 4.5 Series-first | 132
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| 4.5.1 Disadvantages of series-first | 132
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| Higher cost | 132
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| Worse performance | 133
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| Equalizing inrush current | 135
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| 4.5.2 Perceived advantages of series-first | 135
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| Flexibility | 136
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| Redundancy | 136
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| Modularity | 137
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| 4.5.3 Actual advantages of series-first | 137
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| 4.5.4 Current in series-first | 137
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| Fuse per string | 137
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| 4.5.5 Voltage in series-first | 138
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| 4.5.6 Mismatched strings, mixing battery types | 138
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| Mismatched strings | 138
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| Different types of batteries | 138
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| 5 Li-ion BMSs | 141
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| 5.1 BMS introduction | 141
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| 5.1.1 BMS definition | 141
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| Not a BMS | 141
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| A BMS is not optional | 142
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| A BMS is not a charger | 142
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| 5.1.2 BMS type | 142
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| 5.1.3 BMS topologies | 144
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| 5.1.4 BMS format | 148
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| 5.2 Analog protector BMS, Protector Circuit Module (PCM) | 148
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| 5.2.1 PCM placement | 148
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| 5.2.2 PCM functionality | 150
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| Voltage protection | 150
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| Current protection | 151
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| Temperature protection | 151
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| Protector switch | 151
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| Fuse | 151
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| Balancing | 151
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| 5.2.3 Protected 18650 batteries | 151
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| 5.2.4 Charger / PCM combo | 152
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| 5.3 Digital protector | 152
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| Small batteries | 153
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| Medium batteries | 153
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| Large batteries | 153
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| 5.4 Digital BMU | 153
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| 5.4.1 Digital BMS States | 154
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| 5.4.2 Digital BMS functions | 155
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| 5.5 Measurement | 156
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| 5.5.1 Cell voltage | 156
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| Range | 156
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| Measurement accuracy and resolution | 156
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| Measurement rate | 157
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| Fault protector | 157
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| 5.5.2 Additional voltages | 158
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| 5.5.3 Temperature | 158
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| 5.5.4 Current | 159
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| Current sensors | 159
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| 5.6 Current limits and turn off, warnings and faults | 160
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| 5.6.1 Current limits | 160
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| 5.6.2 Current turn off | 160
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| 5.6.3 Warnings and faults | 161
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| Cell voltage, temperature, current | 161
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| Other causes | 162
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| 5.7 Balancing | 162
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| 5.7.1 Required balance current | 162
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| 5.7.2 Balance technologies: dissipative vs charge transfer | 164
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| "Passive" and "active" balancing | 165
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| Dissipative balancing | 165
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| Charge transfer balancing | 166
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| 5.7.3 Charge transfer topologies | 166
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| 5.7.4 Balancing algorithms | 170
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| Voltage based, top balancing | 171
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| SoC based balancing | 172
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| 5.7.5 Charging during top balancing | 172
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| Reduce charger current | 173
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| Turn charger off and on | 173
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| 5.7.6 Redistribution | 174
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| Converter power | 176
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| Redistribution vs. additional cells | 176
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| Redistribution benefits | 176
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| 5.8 Evaluation | 177
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| 5.8.1 State of Charge evaluation | 177
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| SoC evaluation methods | 177
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| 5.8.2 Effective capacity evaluation | 179
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| 5.8.3 OCV evaluation | 180
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| 5.8.4 Resistance evaluation | 181
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| Cell resistance | 181
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| Battery resistance | 182
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| 5.8.5 State of Health evaluation | 182
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| 5.8.6 State of Power evaluation | 182
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| 5.8.7 Ground fault evaluation | 182
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| 5.9 Data logging | 182
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| 5.10 Control outputs | 183
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| 5.10.1 Protector switch and precharge control | 183
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| 5.10.2 Thermal management control | 183
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| 5.11 Inputs and outputs | 184
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| 5.11.1 Power supply inputs | 184
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| 5.11.2 Power supply outputs | 185
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| 5.11.3 Analog inputs | 185
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| 5.11.4 Analog outputs | 185
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| 5.11.5 Digital inputs | 186
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| 5.11.6 Logic outputs | 186
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| 5.11.7 Power outputs | 186
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| 5.12 Communication links | 187
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| 5.12.1 Physical and data layer | 187
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| 5.12.2 Application layer | 188
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| USB, RS232 | 188
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| ModBus | 189
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| Standard CAN based protocols | 189
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| 5.12.3 Wireless | 189
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| Bluetooth | 189
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| WiFi | 189
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| 5.13 BMS sourcing | 190
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| PCMs | 190
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| BMUs | 190
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| Switching to a different BMS | 191
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| 6 Li-ion batteries | 193
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| 6.1 Introduction | 193
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| 6.1.1 Battery definition | 193
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| 6.1.2 Battery use classification | 194
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| 6.1.3 Battery design checklist | 195
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| 6.1.4 Avoiding pitfalls | 195
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| 6.1.5 Should you design a battery? | 195
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| 6.2 Component selection | 195
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| 6.2.1 Cells and BMS | 195
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| Small run | 197
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| Volume production | 197
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| 6.2.2 Other components | 197
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| 6.3 Cell installation and interconnection | 197
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| 6.3.1 Small cylindrical | 197
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| Physical arrangement | 197
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| Mounting | 199
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| Interconnection | 200
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| Sensing | 200
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| Cooling | 201
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| Enclosing | 201
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| 6.3.2 Large Prismatic | 202
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| Physical arrangement | 202
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| Mounting | 203
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| Interconnections | 204
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| Sensing | 204
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| Cooling | 205
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| Enclosing | 205
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| 6.3.3 Pouch | 205
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| Physical arrangement | 205
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| Mounting | 205
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| Interconnection | 206
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| Sensing | 207
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| Cooling | 207
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| Enclosing | 207
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| 6.3.4 Small prismatic, large cylindrical | 208
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| 6.4 BMU Power supply source | 208
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| 6.5 Sensing | 209
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| 6.5.1 Cell voltage sensing, temperature sensing | 209
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| Wired BMS | 209
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| Mated bank boards and PCMs | 209
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| Distributed cell boards | 210
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| 6.5.2 Current sensing | 210
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| Resistive current sensing | 210
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| Hall Effect sensor measurement | 211
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| Two current sensors | 212
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| 6.6 Communications | 213
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| 6.6.1 External communications | 213
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| Can bus | 213
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| RS485 | 214
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| RS232 | 214
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| USB | 214
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| 6.6.2 Internal communications | 214
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| Slave bus | 214
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| Bank harness | 215
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| 6.7 Protection | 215
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| 6.7.1 Protection is required | 215
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| 6.7.2 Protector switch topologies | 216
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| Dual switch, single port topology | 218
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| Dual port topology | 219
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| External switch topology | 220
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| External control topology | 221
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| 6.7.3 Protector switch components | 221
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| 6.7.4 Solid state protector switch circuits | 223
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| MOSFETs | 223
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| Two MOSFETs, single port topology | 223
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| Two MOSFETs, dual port | 224
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| 6.7.5 Contactor protector switch circuits | 225
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| Contactors | 225
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| Two contactors, single port | 226
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| Two contactors, dual port | 227
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| Fault contactor | 228
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| 6.7.6 Hybrid protector switch circuit | 228
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| 6.8 Precharge | 229
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| 6.8.1 Inrush current without precharge | 229
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| 6.8.2 Consequences of skipping precharge | 231
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| EMP | 231
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| Current | 231
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| 6.8.3 Precharge circuit | 232
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| 6.8.4 Precharge components | 233
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| Precharge resistor | 233
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| Alternatives to resistor | 234
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| Precharge relay | 235
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| 6.8.5 Precharge responsibility | 235
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| 6.8.6 Post-discharge | 236
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| 6.9 Battery isolation and ground faults | 236
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| 6.9.1 Battery isolation | 236
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| The case for battery isolation | 237
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| When to isolate a battery | 237
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| Isolated battery in grounded application | 238
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| Isolating a battery | 239
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| 6.9.2 Ground faults | 239
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| Types | 239
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| Causes | 240
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| Consequences | 240
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| 6.9.3 Automatic ground fault detection | 240
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| Types | 240
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| Detection thresholds | 241
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| Ground fault detection requirement | 241
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| Static DC isolation loss tests | 241
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| Dynamic DC isolation loss tests | 242
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| AC isolation loss tests | 243
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| Soft ground fault current test | 243
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| Ground fault detectors | 245
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| 6.10 Thermal management | 245
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| 6.10.1 Introduction | 245
|
| 6.10.2 Internal heat generation | 245
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| Estimation | 246
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| Measurement | 247
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| 6.10.3 Thermal management mechanisms and techniques | 247
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| 6.10.4 Thermal Insulation | 248
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| 6.10.5 Passive heat transfer | 249
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| 6.10.6 Active heat transfer - forced air | 249
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| Forced air ventilation | 250
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| External air path | 250
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| Air flow speed | 251
|
| Temperature gradients | 252
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| 6.10.7 Active heat transfer - liquid cooling | 253
|
| 6.10.8 Internal equalization | 254
|
| 6.10.9 Temporary heat storage | 254
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| Thermal capacity storage | 255
|
| Phase change material storage | 255
|
| 6.10.10 Heating | 256
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| 6.10.11 Heat pumping, cooling | 256
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| 6.10.12 Noise reduction | 257
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| 6.11 Mechanical design | 258
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| 6.11.1 Enclosure | 258
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| 6.11.2 Design for service | 258
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| 6.12 Batteries with capacitors | 259
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| 6.12.1 Directly in parallel | 259
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| 6.12.2 Through DC-DC converter | 260
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| 7 Modules and arrays | 263
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| 7.1 Introduction | 263
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| 7.1.1 "Hey, I have an idea!" | 263
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| The lead acid legacy | 264
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| 7.1.2 ESS subdivision | 264
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| Single battery vs multiple batteries | 266
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| Single enclosure vs multiple enclosures | 266
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| 7.2 Battery with selectable number of strings in parallel | 266
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| 7.3 Modular battery | 267
|
| Case studies | 268
|
| 7.4 Expandable battery | 269
|
| Case studies | 270
|
| 7.5 Battery array | 270
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| 7.5.1 Array-capable BMS | 272
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| 7.5.2 Array master | 273
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| 7.5.3 Voltage equalization | 274
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| 7.6 Ganged batteries | 275
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| 7.6.1 Single bus circuit | 276
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| System operation | 277
|
| Battery description | 277
|
| Operation | 278
|
| 7.6.2 Dual bus circuit | 279
|
| System description | 279
|
| System operation | 279
|
| Battery description | 280
|
| Operation | 280
|
| 7.7 Split battery | 281
|
| Case studies | 282
|
| 7.7.1 Parallel charging, series discharging | 282
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| 7.7.2 Distributed charging, balance charger | 284
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| 7.8 Li-ion and lead-acid | 285
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| 7.8.1 Lead Acid replacement. | 285
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| No way to control and stop charging or discharging | 286
|
| Requires the presence of a battery to operate | 286
|
| Same port for charging and discharging | 286
|
| The charger operates autonomously following to a profile designed for lead acid | 286
|
| Low voltage power supply for the BMS electronics | 286
|
| 7.8.2 Parallel Hybrid L.A. / Li-ion systems | 286
|
| LFP cells | 287
|
| NMC cells | 287
|
| Dangers | 288
|
| Load sharing | 288
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| 7.8.3 Sequential Hybrid L.A. / Li-ion systems | 290
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| 8 Assembly | 295
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| 8.1 Introduction | 295
|
| 8.2 Safety | 295
|
| 8.2.1 Work environment | 295
|
| 8.2.2 Tools and conduct | 296
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| 8.2.3 Emergency plan | 296
|
| 8.3 Preparation | 297
|
| 8.3.1 Harnesses | 297
|
| 8.3.2 Cell pre-balancing | 298
|
| Energy and power battery, charge cells individually | 298
|
| Energy and power battery, charge cells in parallel | 298
|
| Buffer battery pre-balancing | 299
|
| 8.3.3 Terminal preparation | 299
|
| 8.4 Assembly | 299
|
| 8.4.1 Safety tips | 300
|
| Wire insulation | 300
|
| Fastening | 300
|
| 8.4.2 Battery assembly | 300
|
| Single-cell battery, pouch, open assembly | 300
|
| Single cell, small cylindrical | 301
|
| Small multi-cell battery, small cylindrical | 301
|
| Self-balancing scooter battery, small cylindrical cells | 302
|
| Medium sized battery, small cylindrical cells | 303
|
| Small multi-cell battery, pouch | 304
|
| 24 V battery, large prismatic cells | 305
|
| EV conversion traction pack, large prismatic cells | 306
|
| Large stationary low voltage battery, large prismatic cells | 307
|
| 40 V block, pouch cells | 308
|
| 8.4.3 BMS installation | 309
|
| Integrity of electronic assemblies | 309
|
| Wired BMS cell voltage sensing | 309
|
| Distributed BMS cell boards | 310
|
| Banked BMS board | 311
|
| 8.5 Gross balancing | 311
|
| 8.5.1 Manual balancing | 311
|
| 8.5.2 Top balance with a gross balancer | 312
|
| 8.6 Initial testing | 313
|
| 8.6.1 Battery isolation test | 313
|
| General test procedure | 313
|
| Protector BMSs, powered by the battery, no data port | 315
|
| Same as above, with data port | 315
|
| Centralized BMU, powered by the battery | 315
|
| Same as above, powered externally | 315
|
| Wired master/slave BMS, powered by the cells | 315
|
| Same as above, powered externally | 316
|
| Distributed BMS | 316
|
| Distributed master/slave BMS | 316
|
| 8.6.2 Basic electrical test | 316
|
| 8.7 Configuration | 316
|
| 8.8 Functional testing | 318
|
| 9 Dysfunctions | 321
|
| 9.1 Introduction | 321
|
| 9.1.1 Damage | 321
|
| 9.1.2 Troubleshooting and repair | 321
|
| 9.1.3 Resources | 322
|
| 9.2 Cell damage | 323
|
| 9.3 BMS damage | 323
|
| 9.3.1 Disconnected from cell | 324
|
| Before installation | 324
|
| Miswired cell voltage sensing | 324
|
| Installing to a battery that is not completely disconnected from anything else | 325
|
| Connection opens between cells | 326
|
| 9.3.2 Noise | 327
|
| Tap wires are antennas | 327
|
| Voltage across bus bars | 328
|
| 9.3.3 Transitional spikes | 328
|
| Negative spikes | 328
|
| Positive spikes | 329
|
| BMS sensitivity to over-voltages | 329
|
| Problem reduction | 330
|
| 9.3.4 Over-discharge and reversal | 330
|
| 9.3.5 Over-charge | 331
|
| 9.3.6 Other BMS damage | 331
|
| Shorts circuits | 331
|
| Power supply inputs and outputs | 333
|
| Driver outputs | 333
|
| Relay dry contacts | 333
|
| Communication ports | 333
|
| Signal inputs | 333
|
| Mechanical damage | 334
|
| 9.4 Battery damage | 334
|
| 9.4.1 Protector switch | 334
|
| 9.5 Power up troubleshooting | 335
|
| 9.5.1 No BMS power | 335
|
| 9.5.2 BMS power cycles constantly | 336
|
| 9.5.3 Warnings and faults troubleshooting | 337
|
| 9.5.4 Current limits troubleshooting | 338
|
| 9.6 Measurements troubleshooting | 338
|
| 9.6.1 Cell voltage troubleshooting | 338
|
| 9.6.2 Wired BMS troubleshooting | 339
|
| Missing bank | 339
|
| Slowly drifting cell voltage reading, full scale or 0 V | 339
|
| 9.6.3 Distributed BMS troubleshooting | 339
|
| All banks are missing | 339
|
| One bank is missing all the time | 339
|
| Missing bank in the presence of noise | 340
|
| Missing line of cell boards | 340
|
| Missing cell board | 340
|
| Cell missing in the presence of noise | 341
|
| Doesn't report for awhile, after the contactor closes | 341
|
| Extra cells | 341
|
| One board reports minimum or maximum voltage | 341
|
| 9.6.4 Battery voltage troubleshooting | 341
|
| 9.6.5 Temperature troubleshooting | 342
|
| 9.6.6 Current troubleshooting | 342
|
| 9.7 Mismatched cell voltages troubleshooting | 343
|
| 9.7.1 Identify the cause | 343
|
| 9.7.2 Address the cause | 344
|
| Not balancing | 344
|
| Incorrect measurement | 345
|
| Low capacity | 345
|
| String balance | 345
|
| 9.8 Evaluated data troubleshooting | 346
|
| 9.8.1 State of Charge troubleshooting | 346
|
| 9.8.2 Actual capacity troubleshooting | 347
|
| 9.8.3 Actual resistance troubleshooting | 347
|
| 9.8.4 State of Health troubleshooting | 347
|
| 9.9 CAN bus troubleshooting | 347
|
| 9.9.1 No communications | 347
|
| Check the configuration | 348
|
| Ohmmeter testing | 348
|
| Voltmeter testing | 348
|
| CAN adapter testing | 349
|
| 9.9.2 Poor noise immunity | 349
|
| Troubleshooting | 350
|
| Minimize EMI sensitivity | 350
|
| Minimize EMI emissions | 350
|
| 9.10 Troubleshooting other communications | 350
|
| 9.10.1 Windows GUI troubleshooting | 350
|
| RS232 | 351
|
| 9.10.2 Command line terminal | 351
|
| 9.10.3 Slave communications | 351
|
| 9.11 Ground faults troubleshooting | 352
|
| 9.12 Troubleshooting inputs and outputs | 353
|
| 9.12.1 Digital inputs troubleshooting | 353
|
| 9.12.2 Analog inputs troubleshooting | 353
|
| 9.12.3 Logic outputs troubleshooting | 354
|
| 9.12.4 Relay outputs troubleshooting | 354
|
| 9.12.5 Analog outputs troubleshooting | 354
|
| 9.12.6 Open drain drivers troubleshooting | 354
|
| 9.13 Troubleshooting power circuits | 356
|
| 9.13.1 Contactors troubleshooting | 356
|
| 9.13.2 Precharge troubleshooting | 357
|
| 9.14 Repair | 357
|
| 9.14.1 Safety procedures | 357
|
| 9.14.2 Cell replacement | 357
|
| 9.14.3 Gross balancing in the field | 358
|
| 9.14.4 BMS repair | 358
|
| PCM and centralized BMU replacement | 358
|
| Slave replacement | 358
|
| Cell board replacement | 358
|
| Bank board replacement | 359
|
| Component level repair | 359
|
