sunnuntai 20. huhtikuuta 2014

Parallel balancing

Just thought I'd show you what's going on. The 60 Ah batteries had arrived while I was gone and once I got back I started taking the shipment apart. Everything was there. Including the 25 pcs SE60AHA cells, a 4x20Ah 12V block, interconnects and a PowerLog 6S, which I may or may not need anymore. Thanks to my smallest offspring for helping out.

Couldn't have done with out you.

Having moved the batteries to the basement I proceeded to do a little experiment in parallel bottom balancing. Here I have the 60 Ah cells connected to each other in parallel. The 40 Ah cells are lower in charge, but once I get the sixties closer to them I may go ahead and parallel all of them and then proceed to drain them together to around 2.7 volts. Should be pretty well in balance then.

Sure looks like a lot of cells when you line them up like this.

Oh, one more thing. I thought this was pretty funny. Or sad. Can't decide which.

Personally I'd rather be on a plane with these batteries than most people.

3 kommenttia:

  1. Have you thought about this parallel initial charging, is it necessary? Although you probably don't have a laboratory power supply, and neither do I. I've tried to find one but they tend to cost a small fortune here in Finland.

    1. No, what that does is that it top balances the cells, which is exactly opposite of what we want to do, which is to bottom balance the cells.

      If you did that you'd have to restart the whole bottom balancing process again.

    2. I suppose if you charge to a low enough voltage, like 3.5 volts per cell, it doesn't do any harm, so if you feel your really want to do it, you can, but personally I wouldn't bother. It doesn't really differ much form just charging the whole pack normally and then bottom balancing, if this initial charging is something you feel you want to do. I don't think their recommendation to do it is really based on anything though. Besides they advocate a lot of stupid stuff anyway.