No BMS needed for charging

I’ve seen some builds not needing to use a BMS for charging their 18650 battery packs given that they rarely drift if taken care of properly. Does the same thing apply to LiPos?

Under no circumstances should you run a lipo pack without some form of balancing, either in the form of a BMS or a balance charger. That’s just asking for a fire.

I wouldn’t even charge a 18650 pack without balancing, the consequences of failure are simply too high.

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Only very stable chemistry cells can be used without bms. Sony konion and Tesla for example. But even like that a bms is needed for hvc lvc. MD is right, under no circumstance Skip balance on lipo. Fire hazard!

I heard Lifepo4 cells could be used without balancing, but it is not recommended…Can somebody confirm that?

maybe if you draw like 0.1A from your battery you wont need balancing but if you draw 40-100A like we do its totally needed its like 30$ why cheap out on a part that protects your 200$+ battery

I’ve been runing my 12s4p daily for 3 months, no BMS at all, charging up to 50v and discharging once in a while to 36v, most of the days I just go down from 100% to 70% and charge.

Yesterday I opened the enclosure and find out the cells are exactly as I left them when I started the build, no. Drifting at all.

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Only joking, but didn’t one of your boards catch on fire @Eboosted?

I think he means drifting voltages bud? @Eboosted

I was referring to the @MysticalDork 's concerns of fire hazards. @mynamesmatt

ANY of these batteries can be charged without balancing. A FEW TIMES. They need to be balanced at least every few charges. There is little to no harm running it a time or two without balance.

Now if you misread what I wrote as “I think I can probably run it 25 more times because he said a few was okay” then you will have a fire eventually.

If you need to go through the effort to balance it all the time, you might as well just build the balancing into the charge procedure – which typically means using a BMS.

@neverpush i was referring to eboosted talking about cells drifting in his enclosure but you guys mean drifting voltages…right?

That is correct.