Electric vehicle battery monomer importance sampling
The consistency of electric vehicle battery monomer decided the whole battery of subsequent life, monomer voltage, electrolyte density, the reaction is balanced capacity and the battery for the whole state, each battery voltage, the smaller the difference between lowest and highest voltage, battery more balanced, the greater the difference, that the imbalance in the early stages of the group of the monomer battery performance indicators, including: resistance, electric properties of electrode, electrical connections, the temperature characteristic, decay rate, etc. , is not the same as the above factor, will directly affect the output electrical parameters in the operation of the differences.
Electric vehicle battery monomer, after made itself exists certain performance difference, initial degree of inconsistency with the battery in the process of using continuous charging and discharging cycle and cumulative, cause each monomer battery status (
SOC, voltage, etc. )
Have a greater difference;
Using the environment within the battery pack for each single cells are also different.
This can lead to inconsistent degree of monomer battery in the use of step by step in the process of amplification, which in some cases made some monomer battery performance acceleration attenuation, and eventually lead to premature failure of the battery pack is not consistency reasons from the time order.
Monomer batteries in the battery inconsistency is mainly manifested in two aspects: the problem on the process and material in the manufacturing process of uneven, makes the battery plate activation degree of active material and thickness, pore rate, even a very small differences, partition, etc, to produce on the internal structure and material is not completely consistent;
Loading when using the battery pack and the battery electrolyte density, temperature and ventilation, self-discharge according influence degree and the charging and discharging process.
New monomer in the set of process measures to ensure the battery pack use unified specification, type of battery, ensure the quality of the battery factory especially the consistency of the initial voltage filter condition: voltage;
Battery into data;
Consistency evaluation method has a lot of, use the set time interval by each testing point form the shape of the battery charge and discharge curves for scientific classification, distance, area, so as to determine the consistency of the battery in the subsequent use of process, the proposal checks a 2 months electric vehicle battery voltage, density, etc. , these data are not consistent or gap is too big, the need for equalizing charge or is charging method.