Battery module capacity estimation method

Abstract

The invention discloses a method for estimating the capacity of a battery module. The method comprises the following steps: acquiring a charging cut-off temperature of each single battery in a battery module at a respective charging cut-off moment; obtaining a theoretical capacity value and an actual SOC value of each single battery at the respective charging cut-off temperature; and calculating the chargeable electric quantity and dischargeable electric quantity of each single battery according to the theoretical capacity value and the actual SOC value of each single battery at the respective charging cut-off time temperature so as to obtain the capacity of the battery module. According to the method provided by the invention, the discharge capacity of the module can be estimated according to the voltage of each single battery and the capacity of the single batteries forming the module when the battery module is assembled without charging and discharging the module, so that the time for obtaining the capacity of the module is greatly shortened, the efficiency is improved, the purchase cost of charging and discharging equipment of a production line is saved, additional hardware setting is not needed, and the cost is reduced. The cost is low.

Description

technical field [0001] The invention relates to the technical field of batteries, and relates to a method for estimating the capacity of a battery module. Background technique [0002] As a new type of alternative energy, secondary batteries are widely used in many fields such as electronic products and electric vehicles. Generally, after the battery cell is produced, it needs to be matched into a battery module and put into use. The battery module is generally formed by several or hundreds of single cells in series and / or parallel. [0003] Battery modules generally need to be tested before leaving the factory. The existing module capacity estimation is based on the overall characteristics of the module, according to the relevant characteristic points on the charge-discharge curve, to estimate the overall capacity by charging and discharging part of the capacity. This method is used to estimate the overall capacity. The capacity test of the battery module includes the proc...

AI Technical Summary

Problems solved by technology

[0003] Battery modules generally need to be tested for capacity before leaving the factory. The existing module capacity estimation is based on the overall characteristics of the module, and according to the relevant feature points on the charge-discharge curve, the overall capacity is estimated by charging and discharging part of the capacity. This method is The capacity test of the battery module includes the processes of full charging and emptying, so the whole process takes a long time, which greatly increases the manufacturing cycle of the module and brings loss of site, personnel, equipment and energy consumption