Charging battery while ESC connected at 21V? Opinions

ESK8 Electronics
#1

Hey, So I want to have 2 5S4P packs wired in series to operate the board and then wired in parallel to charge the battery.

So what I had thought of was to have my anti-spark switch between the 2 packs, to disconnect the series connection for charging and connecting the two packs in parallel.

Diagrams below…

IMG_1467.JPG3264×2448 1.98 MB

My question is, is it ok to charge while the ESC is on at 18-21v or should I have a second loop key to disconnect the esc while charging. Can I set any settings on the ESC to make it safe (low voltage cutoff?)

The reason I want to charge like this is because I only have 8S balance chargers and my BMS/Charger is not scheduled to arrive until mid January…

#2

@chaka, @JLabs, @psychotiller, @barajabali You guys are pretty savvy, any input?

#3

The esc doesn’t have any way to offer any input to charging…I honestly wouldn’t do what you’re trying to do. If you have an 8s balance charger you can charge one 5s side at a time.

#4

Not sure I follow. I would be charging with a balance charger. Thing is, I would connect the packs in parallel to charge while the ESC is connected (so I don’t have to open the enclosure…) and it would see ~21v while charging.

#5

The esc isn’t a factor as long as you have a fail safe set in the receiver so you’re board doesn’t take off on you

1 Like
#6

If I set my low voltage cutoff in the setup as 28V, that should not be possible correct?

I just don’t want to fry the thing. Lol

#7

That’s what I’m trying to explain to you . Your esc. Isn’t part of the charge system. Only part of the discharge system.

#8

But the ESC is plugged in in the charge system, how is it a no factor? Is it because of the failsafe on the receiver?

#9

No it’s not. Why would it be? It should just be plugged to the battery right?

#10

Ok. I see. The problem is you have your loop key in the wrong spot. It should be in either the red or the black wire right before the esc.

1 Like
#11

Yes but then when I remove the loop key, the pack is still a 10S pack which is why I placed it where I did.

The functional diagram is the one on the bottom right… I can add a second loop key but it’s what I was trying to avoid.

#12

Ok, it works with the second loop key :slight_smile:

#13

I was battling with the same decision. I ended up just adding a second loopkey to be safe. I used an xt90 antispark for the esc loop key, then a male xt60 for the series connector and female xt60 for the second charge connector, at least that way it can only plug in one way.

1 Like
#14

I did similar. Will post pics later