kdog
10 kW
@LTRMB
In my very rudimentary test, I was surprised at how much heat started to be generated once the optimal rate had been exceeded. OR is right we don't use cont current but every time you exceed the limit heat start being generated quite quickly. Given your battery is sealed (usually) heat builds up. Cheap battery packs get away with it cause the batteries can soak up the heat but they're not designed to be heat sinks, and, the hot spots on the battery ends are where the trouble starts.
The series connections take the full load but the parallel connections you'll have to figure out. In perfect arrangement ( ie. one series connection for each parallel group and a +/- distributing loom at each end) the P connections see virtually nothing- just balancing currents.
In my 20s5p build rated to 60A cont discharge I used .1mm copper for the series connections (5 of them- one for each P group) but I only needed a single strip of .15x8mm nickel for the P connections. I used a copper tab at each end and had a fat copper bus to join them so I had equal sharing in/out of the pack.
In a poor layout a P connection could see up to : total amps/ #P attached to it (ie full out put of those cells)
Size your connectors accordingly. Geometric shape ( space available) is a determining factor in how you can lay the pack out
The best way around the whole problem ( but only if you are not using holders ) is a really wide strip that does the P and S connection all at once- search Madin88 's builds.
K
In my very rudimentary test, I was surprised at how much heat started to be generated once the optimal rate had been exceeded. OR is right we don't use cont current but every time you exceed the limit heat start being generated quite quickly. Given your battery is sealed (usually) heat builds up. Cheap battery packs get away with it cause the batteries can soak up the heat but they're not designed to be heat sinks, and, the hot spots on the battery ends are where the trouble starts.
The series connections take the full load but the parallel connections you'll have to figure out. In perfect arrangement ( ie. one series connection for each parallel group and a +/- distributing loom at each end) the P connections see virtually nothing- just balancing currents.
In my 20s5p build rated to 60A cont discharge I used .1mm copper for the series connections (5 of them- one for each P group) but I only needed a single strip of .15x8mm nickel for the P connections. I used a copper tab at each end and had a fat copper bus to join them so I had equal sharing in/out of the pack.
In a poor layout a P connection could see up to : total amps/ #P attached to it (ie full out put of those cells)
Size your connectors accordingly. Geometric shape ( space available) is a determining factor in how you can lay the pack out
The best way around the whole problem ( but only if you are not using holders ) is a really wide strip that does the P and S connection all at once- search Madin88 's builds.
K