Detail of GB/T 43695-2024

Introduction of GB/T 43695-2024

Energy conversion efficiency requirements and measurement methods for lithium ion cells and batteries 1 Scope This document specifies the energy conversion efficiency requirements and for lithium ion cells and batteries, and describes the calculation and measurement methods. This document is applicable to lithium ion cells and batteries. 2 Normative references No normative references are listed in this document. 3 Terms and definitions For the purposes of this document, the following terms and definitions apply. 3.1 lithium ion cell device that realizes mutual conversion between chemical energy and electrical energy by moving lithium ions between cathode and anode, and is designed to be rechargeable Note: This device consists of an assembly of electrodes, separators, electrolyte, container, terminals, etc. 3.2 lithium ion battery assembly ready for use which comprises one or more lithium ion cells Note: This assembly includes protective circuits and may also contain encapsulating materials, connectors, protective devices, etc. 3.3 coulombic efficiency η percentage of the charge output at which a battery is discharged to the charge input at which it is charged Note 1: Unless otherwise specified, the coulombic efficiency in this document specifically refers to the efficiency at equal magnification. Note 2: Coulombic efficiency is also called charging/discharging efficiency. Note 3: In this document, "battery" refers to lithium ion cell. [Source: GB/T 2900.41-2008, 482-03-14, modified] 3.4 energy efficiency η percentage of the energy output at which the lithium ion cell is discharged to the energy input at which it is charged Note: Unless otherwise specified, the energy efficiency in this document specifically refers to the efficiency at equal magnification. [Source: GB/T 2900.41-2008, 482-05-53] 3.5 constant voltage charge charge that maintains a constant voltage during charging regardless of charging current and temperature [Source: GB/T 2900.41-2008, 482-05-49, modified] 3.6 constant current charge charge that the current remains constant during charging regardless of the voltage or temperature of the battery [Source: GB/T 2900.41-2008, 482-05-38] 3.7 rated capacity C capacity value of a cell or battery declared by the manufacturer Note: It is expressed in ampere-hours (Ah) or milliampere-hours (mAh). 3.8 charge capacity Cc charge input to the battery under specified charging conditions 3.9 discharge capacity Cd charge output to the battery under specified discharge conditions Note: The international unit of charge (or amount of electricity) is Coulomb (1 C = 1 As), but in practice, battery capacity is usually expressed in ampere hour (Ah). [Source: GB/T 2900.41-2008, 482-03-14] 3.10 cell (battery) energy E power input/output of the cell (battery) under specified conditions [Source: GB/T 2900.41-2008, 482-03-21, modified] 3.11 charge energy Ec electrical energy input of the cell under specified conditions 3.12 discharge energy Ed electrical energy output of the cell under specified conditions Note: The international unit of energy is Joule (1 J = 1 Ws), but in practice, battery energy is usually expressed in watt hours (Wh) (1 Wh = 3,600 J) [Source: GB/T 2900.41-2008, 482-03-21] 3.13 reference test current It test current with the same value as the rated capacity (C) Note: It is expressed in ampere (A) or milliampere (mA). 3.14 limited charging voltage Ucl rated maximum charging voltage of a cell or battery as declared by the manufacturer 3.15 end of discharge voltage Ude voltage at the end of discharge of a cell or battery as recommended by the manufacturer 3.16 recommendation charging current Icr constant-current charging current recommended by the manufacturer 3.17 recommendation discharging current Idr continual discharging current recommended by the manufacturer 4 Test conditions 4.1 Environmental conditions of tests Unless otherwise specified, the tests are generally conducted under the following conditions: a) Temperature: 23°C ± 2°C; b) Relative humidity: ≤ 90%; c) Air pressure: 86 kPa ~ 106 kPa.

Contents of GB/T 43695-2024

Contents Foreword i 1 Scope 2 Normative references 3 Terms and definitions 4 Test conditions 4.1 Environmental conditions of tests 4.2 Parameter measurement tolerances 4.3 Sample pretreatment 4.4 Sample requirements 4.5 Quantity of samples 5 Representation and calculation methods 5.1 General 5.2 Capacity 5.3 Energy 5.4 Coulombic efficiency 5.5 Energy efficiency 6 Requirements and measurement methods 6.1 Coulombic efficiency 6.2 Energy efficiency Bibliography