Alright everyone, I bought a new charger recently that came with a paraboad.
Couple questions. Can I plug the paraboard into the balance board and then plug the balance board into the charger, So Im able to charge two 3s batteries.. or three 2s batteries. Check out the photo.. The paraboard's plug doesnt really fit that good into the charger so I figured it would work out this way? yes?



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If so, Next question is. Charging two 3S batteries, both 5000mah. How would I set up the charger? Would I set max amps at what the total amount or is the amps set per battery. For example If I set the charger at 20amps. Would it charge each battery at 20amps or would it charge each battery at 10amps? Same question goes for the "mah" setting. Woukd I set it at 10000mah or 5000mah?

Thanks.

Can anyone verify if im right? Id like to get my batteries charged. But I dont wanna mess something up. Thanks.

You can use the balance board as long as the connectors are the same type. Should be able to plug it directly into the charger if the same is true. Balance boards can also be used to convert plug types.

In parallel the amps split. 20 amps from the charger is 10 amps into each of two batteries. Two 5,000mAh in parallel become a 10,000mAh, of the same voltage. 20 charger amps is a 2C charge rate on a pair of 5,000mAh batteries in parallel.

Ok thanks. As Long as I dont charge three 3s batteries the way I have mine set up it should be good right? Since my paraboard is plugged into the 6S port on my balance board and then into the charger that means I cant charger anything above 6s total right? Or doesn't that matter?

You should be able to charge three batteries at the same time, or even four it looks like, with that paraboard. Ideally at somewhat similar voltage before starting.

Just have to be the same cell count. Up to four 3S, or up to four 2S. But no mixing of 2S and 3S at the same time!

And yes, it appears you are limited to 6S batteries with that setup best I can tell. 7 wires going to the charger, and between board and paraboard, right?

A picture for reference. With a six position version, charging 2S.

Yup 7 wires. No problem tho, I dont plan on charging more then 6s at once. Either my two 2s batteries or two 3S batteries.

Last question. Since I can never seem to figure out the equation.. I have a 350w power supply. What is the fastest I'am able to charge two 3S 5000mah batteries at the same time. From my understanding...two 3S batteries is 3.7 x 6cells = 22.2v 350w charger divided by 22.v = 15.7amps max? So does that mean each battery would only charge at 7.88amps max?

EDIT. Scratch that... 15.7amps would be the max. Not 7.88amps. No need to divide it since 22.v is the total.

Right?


man... I get confused at this stuff. ha

I recommend using the full charge voltage, and accounting for charger efficiency. But you are also accounting for the cells twice in your comments, that’s not needed. EDIT, you got it!

(350W x 80% efficiency) / (3 cells * 4.2V/cell) = ~22.2 amps total. ~11.1A for each battery.

Isn’t that a 20 amp charger? Which is good, as that would leave your 350W power supply a little extra breathing room. 20 amps on the charger, 10A to each pack. Just about perfect, assuming the supply rating is honest.

Your charger factors in as we'll.. It needs a certain voltage to reach its rated charge.

Two 3s in parallel is still 3 cells voltage, just has an increased capacity so it will take longer to charge unless you charge faster. I use 4.2v in my calculations so the result I get will work all the way up to full charge.

So my two 3s 1400mah packs would be one 3s 12.6v 2800mah pack if wired in parallel. 1c would be 2.8 amps. 2.8 * 12.6 tells me I need 35.28 watts. Factor in an extra 10 to 20% for power supply efficiency.

My concern would be sending a lot of current through that tiny balance board. I know from personal experience those little boards cannot take large amps and the connector ribbon between the ports melt. My advice would be start very slow.

Correct me if I'm wrong but did you mean 25.2 instead of 22.2? 350W*80% divided by 25.2 would equal 11.1amps

And just to clarify... 11.1amps would be for each battery? Wouldnt that mean 22.2amps total? Or doesnt that matter? if the charger is set at 11.1amps it would still do 11.1 on each battery at the same time?

Divided by 12.6V, in parallel it’s still a 3S battery:
350W*80% / 12.6V = ~22.2 amps total.

11.1 amps for each battery, yes. And yes, 22.2 amps total, what the charger sees.

If the charger was set at 11.1 amps, each of two batteries sees half, or 5.55 amps, in a parallel hookup.

That's why it's important for the batteries to be at a similar voltage, a similar charge state, before connecting. Good practice to check each before charging every time.

There is a new type of paraboard, that appears to be one but I'm not sure, that has polyfuses to help in the case of a brain dump. But still best to not get in bad habits.

ok, I see what your saying now. I think im getting the "in parallel" and "in series" confused.

For some reason I just assumed since Having two 3S batteries plugged into the paraboard that the charger would think 6S total and charge to 25.2v instead of 12.6

So in theory, (minus the whole, being limited to 6 cells charging becasue of the way i have it set up) I could be charging Four 3s 5000mah batteries at once and it would still technically be (350watt*80%) divided by 12.6 =22.2amps total. But then I would have to divide that by the 4 batteries being changed and that would only be 5.55amps for each battery charging right? I think im starting to get this.. ha

Edit. for my example above, If I were to be doing that, I would have to set my charger to 20000mah right? Again, I know I wouldnt be able to do that since im limited to charging 6 cells at once, its just an example.

Bingo!

(Well except for the charger limit detail, isn't it a 20 amp max charger? But you have the battery thinking part right)

It would be a 20,000mAh battery, yes.

No, you would be able to. It's not a 6 cell total limit, it's only a 6 cell in series limit. All four of the 3S in parallel are still just a 3S to the charger.