What is cell inconsistency?
General speaking, cell inconsistencies refer to important parameters of single internal cell parameters are different in the whole battery life span.
The individual cells in a battery pack have somewhat different capacities, state of charge (SOC) and internal resistance and current of self discharge which will affect battery performance and life length.
Obviously, there is also cell consistency. In ideal condition, SOC of each cell is absolutely the same. That is, every single cell can charge fully and discharge over at the same time.
What causes cell inconsistency?
There are two main aspects:
technology, purity of materials, etc.
- Using environment:
In a pack, every cell is placed in different location, thus every cell has different using environment. For example, temperature will be slightly different, cells will be inconsistency with long term accumulation.
What does battery balancing do?
Battery balancing technology improves battery life by maximizing the capacity of a battery pack with multiple cells in series, ensuring that all of its energy is available for use.
Is battery balancing necessary?
Yes, of course. Balancing is only necessary for packs that contain more than one cell in series. Parallel cells will naturally balance since they are directly connected to each other, but groups of parallel wired cells, wired in series (parallel-series wiring) must be balanced between cell groups.
Battery balance is an important function of BMS. And every lithium ion battery pack has its own BMS. Thus battery balancing is necessary. For other kinds of battery packs, battery balance is a great way to prevent them from overcharging and over-discharging.
Battery balance aims to solve shortcomings of battery itself. It is necessary for them.
Is battery balancing the same as battery charging？