GWL/Team has spent many months testing the active balancers from China. In general, we have found following reasons why to “Say No!” to these products.

1) The risk of a products failure – Low Reliability Several of the balancers simply failed after some time. They either stopped working out of a sudden or they started to discharge the battery constantly.  

2) Low balancing currents – If the voltage difference is small, the balancing current will be small. The voltage difference for LFP cells is usually bellow 0.1V (100mV). This makes the active balancing very ineffective. For large cells >100Ah, you need high balancing currents (3Amp or more). These balancers make only 0.5 Amp or 1 Amp. Limited use with large cells.

3) The risk of a constant discharge – The balancer unit load the battery with a continued discharge. When left at the battery for many weeks (months) unattended, it will slowly discharge the battery completely.

4) Some of the balancers make a hissing noise – The hissing noise is disturbing for the user for house-hold applications. When we asked the supplier, they answer was, the hissing noise is the part of the function. It is acoustic indication of the balancing. Really?

At this moment the solution from GWL is the passive balancing by means of the CBM board.