Need help with charging

Interesting, i’ve heard of people charging large li-ions without a bms, but it is very rare to charge lipos without one, from what i understand. i think the vast majority of people would agree that having a bms on a lipo pack is mandatory.

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Definitely agree with the “you really do need a BMS” statement. The cells are never THAT well balanced, especially long term.

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Yeah I mean it’s all up to you and what you feel comfortable doing.

It works great, all the way up to the huge fire. I mean, even right before that it will work great. :roll_eyes:

You better check each cell voltage with a multimeter at a MINIMUM to verify it’s working as good as you think it is…

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So my full charge is 50.4 and my cut off is at 44.4 volts I have two motors 6374 two vesc from torque boards what’s is a bms how do I find it and wire it right

http://lmgtfy.com/?q=What+is+a+bms second result.

Read this thread:

Lithium battery packs should always be balance charged. Both Lipos and Li-ions.

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If you want to say “second result” then you can’t pick “google” as the search engine because Google gives each person different results. ddg.gg will give the same results for the same query.

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Bms for charge only is mandatory if you ask me on every type of battery Unless you have a balance charger

True, but I’d be willing to wager that Wikipedia is high on everyone’s list.

I pull the enclosure once a month, and check the cells. Each time I do it, they are perfectly balanced. I think the danger of lipos has been blown out of proportion and with some common sense and care, they’re perfectly safe

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So what’s hooks to the bms from the charger

That’s perfectly fine until one of the cells goes bad. Without balancing, the first time you know about it will be when your house burns down.

It’s like parachuting. You can be as careful as you like in packing your parachute (checking your cells), but eventually it’s going to fail to open (a cell will go bad). Without a backup chute (BMS) the results are catastrophic.

Well I guess agree to disagree on battery design. Thanks for your opinion though :grinning:

Wait, what ? Are you sure you understand the possible consequences of charging a Lipo or Li-ion battery without a balance charger or BMS ? I mean, not caring is a thing. But you can’t say that not using a BMS or balance charger is OK and safe.

I’m saying that I routinely check my cells and they have never strayed out of balance. That is the point of a BMS, to keep them in balance, and if my cells stay in balance without one, a BMS is unnecessary.

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Sure, I agree. You should have indicated that in your first post, especially when a newbie is asking for help/advice :slight_smile: And battery are a serious subject due to how dangerous it can be. It’s better to share the whole picture, I think too much information is always better than not enough information.

One thought: I believe cells get out of balance more easily with age and charge/discharge cycles.

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Yeah, that’s fair, I could definitely be more descriptive.

Yeah this is true, I usually get new batteries about once a year. Costs me $100 to get high discharge lipos, when similar range and lower discharge lions would cost $350 to $400. So i figure the cost is about the same long-term (lions last about 3-4 years I believe)

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Yeah, that’s why I went for Lipos too for my first build. It’s also easier to swap, if you ever need to.

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