Mixing Lipos.

Can one of my electric flight friends refresh my failing memory.

I remember reading a couple of years ago on the RCME forum the reason why if say the model is a 10 s powered unit it is advisable to use 2 matched 5 s lipos. Should a 4s 5000mah and a 6s 5000mah be used, what would be the result, and what if any would be the damage caused to the lipos .

Garry

When coupled in series a 4s and a 6s is a 10s providing their capacity and C rating are the same. Indeed you could make up a 10s using any combination of cells (even 10x1s!) providing they are all the same capacity.

The main issue with unequal cell count batteries is charging them. The only way they could be charged from a single charger would be as a 10s but you would have to make sure the balance leads and plugs were organised correctly.

HobbyKing sell a 7s LiPo that has a 4 and 3 JST balance plugs. It caused quite a bit of confusion until they supplied a 4 + 3 into 7 adapter!

Thanks lads, however may have a further problem. Both the 6 s and 4 s packs are 5000 mah but I am sure that the 4s are rated at 20c and the 6s are rated 30c if these are coupled to provide the 10 s requirement what would be the net result of this . The packs would be recharged as separate lipos Simon, not as a 10 s pack . Its now the different c rating that is causing me concern .
I did see the discussion re the HK 7 s packs and the confusion that it caused

Garry