Is it possible to use a dual lipo charger to charge 7s lipo batteries in series (14s).
My charger is rated to 12s but has 2 charge ports built in to it to charge 2 batteries individually at one time however I’m not sure if this is possible in series, my idea is to splice a charge connector(s) in to the series harness.
I don’t think it would work that way because they probably aren’t isolated.
Getting a brick charger or a power supply is probably a much better option than a hobby charger.
No, you can’t do that.
The charger circuitry inside (basically a buck/boost converter) is not isolated from the input, so you can’t put them in series.
Doesn’t matter, same answer as above. No putting the outputs in series.
100% this. Just get a brick.
But probably not at 58.8V, so it doesn’t matter. You can’t use that for a 14S battery.
Sell it and buy a 14S (58.8V) brick charger and a BMS.
if you want to save money you can also use your Charger as a DC power source feeding a DC-DC step up converter. they are cheaper compared to buying a whole new charger.
If saving money is the primary goal, you should exit DIY and buy a Backfire or something.
It depends on what you want. If you want to go over 50km/h and have good power you pretty much have to DIY. If you already have the tools you can definitely save money compared to the crazy expensive prebuild super boards or evolves.
Thanks, I was hoping to do a Trampa like system, less faff of removing the lipos every time I wanted to charge them, I’ve looked at the bms route, may get a smart bms and brick charger at a later date, 14s and above are becoming the next thing so hopefully something convenient comes out. I really wanted to use the charger I have now, really accurate on cell balancing and fast
Then get a 12S lipo system 
(two 6S packs)
It’s not an issue charging 2 7s lipos
Of course it’s not, because it’s designed to charge 7s lipos.
You can’t charge 14s lipos, because it’s not designed to do that.
It’s not a good buy for the long term.
Hobby chargers are a dead end.
Yes, it can charge two separate 7s batteries. It can not charge one 14s battery by using both outputs. Those are two different applications.
That one you linked, is exactly as capable as the one you already have, which is to say not able to do the thing you want.
The one I have now charges both my 6s lipos as 12s through one connector
The one in the picture is pretty much what I already have but can charge 2x7s as 14s
It only needs one output with the 14s charger
Why? I’ve been running them for years
shrugs
I dunno what to tell ya. Maybe the charger designs have gotten more advanced since I last looked.
The last time I looked into lipo chargers, they were just simple non-isolated buck/boost converters and if you tried that you would either destroy the charger, or destroy the battery.
You’d think the documentation would be more clear about what capabilities it has.
