I have two 2s batteries I am using for my rc8.2e. I have them wired I series to get 4s. My question is do I need to charge them individually or can I leave them in series and charge both packs as one? Thanks for the help

I run the same setup. I have found that it is faster to charge them separate rather than as one 4s. But I have done it and it works as long as you are aware of setting your charger to charge 4s.

You need a 4s - 2 x 2s splitter for your balance leads if you plan to balance charge them

Or split the packs and charge them in parallel, a little easier

Cheers

I have the series charging adapter with the balance plugs. Works well but has potential for mixups. I still prefer the one at a time method as it seems faster. Don't need to balance on race days either.