# Cell voltage measuring device

So I’m upgrading from a normal balance charger to a bms and since I won’t use the Imax b6 charger anymore, I don’t really have any way to check battery voltage, each cell’s voltages, and basically anything about the batteries. What device can I buy that will be on the cheaper side, that will be able to check voltages and whatever else may be needed? nothing fancy. just needs to do the job and be reliable. Thanks!

U have multimeter?

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The idea is that the BMS does all this and all you do is plug in a charger. Just like if it’s a laptop computer.

To answer your questions, there isn’t really a device because it’s not needed. You can buy a battery level indicator but it’s for the entire pack voltage, not the individual cell voltages. Leave the charger plugged-in after it turns green and it will balance the cells.

No, I was thinking of getting one, but I couldn’t find one that can check cell voltages and I’m not sure it’s even possible with a bms because the Balance wires are already connected to the bms.

I know how a bms works, but I still need to be able to check the battery’s voltage once in a while, which voltmeter can you recommend for that? Edit: just saw the link, I already have one of those, but only precentage and not volts. Whats the difference between that small indicator and a full size meter though?

If you push the button, it toggles between percentage and volts. There is another button inside, you hold that before you turn it on, then push the front button until it says L10 (lithium metal, 10 series) and then install it. After that the front panel button toggles between percentage and volts

to get individual voltages I think a multimeter is the usual way. you couldn’t get true individual cell voltages since you likely have some paralleled but you can get the whole parallel group

I have this:

You just plug it into the balance connector of your battery and thats it. It shows the total voltage, and each individual cells voltage Hope this helps

All cells in a parallel group will be the same voltage.

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that’s what I’m saying

I’m saying that the true individual cell voltage will be the same. If you disconnect a parallel pack and measure each one, it will always read out the same voltage assuming they’ve been connected for any reasonable amount of time.

yea. I know a paralleled cell will have the same voltage but at that point, measuring a cell that’s paralleled, its’ voltage isn’t telling you much. I guess what I mean by “true” is it’s “useful” voltage as what its voltage reveals about its’ capacity or state of health

10 char

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Yeah so I can check the total and divide that by the number of cells, but the reason I need individual cells voltages is that sometimes the battery doesn’t completely balance the cells, once I had a 0.15v lower in one cell than the rest, and I just want to make sure that doesn’t happen again.

When using a bms, the ballance cables are soldered to the chip, so i have no access to them. Thanks though! Edit: and connected without the actual port, only the cables.

When you use a BMS, it specifically avoids the cells being unbalanced. That’s what a BMS does… that’s why nobody has a ready-made solution for what you want. It’s not needed. You can make it yourself, no problem though…

If you have experience with batteries that don’t have a BMS, like hobby lipos, then that may be why you’ve seen them unbalanced. You can even use a BMS with those as well if you want.

Yeah but isn’t a balance charger supposed to do the same?

The batteries I will soon use with a bms are lipos yeah, hoping the bms will balance them better than the Imax b6

A balance charger will do that, yeah – if you instruct it to. I used an imax B6 once and didn’t realize it was getting unbalanced because I kept putting it on “charge” mode. You have to use “balance” mode at least every few times.

Ive looked into this and u are after is cell meter, i think.

Go on banggood or aliexpress, theres quite a few options

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I was using balance mode, 5 amps.