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[DJW]

Morning All


I've been planning to use a pair of 6S 8,000mAh 15C Turnigy Graphene LiPos in my 1/5 Aquarama build, but the backorder status has now gone to 'No ETA'.


So I can get 4x 6S 4,000mAh 45C units ex stock. And I know that people do use them in parallel, but I've no experience of that. Any comments..?


I realise that the parallel pair would need to be kept at very similar voltage to avoid current leak from one to the other on connection, but after that, can they be treated as one battery..? Charged as one unit, a 6S2P...?


Other options would be to either just swap them out, so just mount a pair and keep a spare pair charged and ready to swap out. Or build in a mount for all 4 and just change over the connections at an appropriate time. The weight would not be an issue.


Be grateful for comments.
Thanks and regards
David.

[JimG]

There will be no problem using them in parallel, larger capacity LiPo pack used to come as a parallel set up before the newerr larger capacity cells became available. QUite recently there were charging boards available allowing you to charge packs in parallel. Just make sure they are all fully charged before connecting them in parallel although a slight difference in charge state will automatically self correct without the massive currents claimed by the parallel detractors.
As a test I connected 2 3S 8000mAh packs in parallel with one full charged and the other flat while monitering the current between the packs. They ended up with both half charged and the maximum current was around 8A, well within the capacity of the connecxtors and the wiring to the batteries with both packs showing no change in temperature after equalising.I have used parallel packs both in boats and aircraft in each case it was a high current use and the packs were warm at the end, no problems were found in all cases. I generally charge the packs individually although it does take longer but does not need such a high current from the charger.
Jim

[DJW]

Hi Jim

Thanks for this. Very reassuring to hear that you've done this before, and the LiPos behaved OK. I've realised that it will also give me options for the layout of the 4 smaller LiPos rather than the two larger (by volume and weight) within the hull. I really like the Turnigy Graphenes, but they do seem hard to get hold of at the moment in many capacities.

I've ordered an Ammo Box (ex NATO 50 Cal...) to keep my LiPos in the hope that it's going to keep them safe...

Thanks again.
David.