Is regenerative breaking bad for battery?

I know exactly what I’m doing! I’m using Cheap BMSs just for charging! I just shared that not all BMSs will Bring back your Unbalanced cells to a fully balanced pack, and everybody went against me :joy:

Just to clear that up (sorry if you already said so, I just did undetstood it different) unbalance cells comming from different things, the regenerative break is the last which will affect it. Maybe if you live in a very hilly area and you go a lot downhill it could have a minimal effect, but if you live for example in New York it’s just super less you charge back. And even than, if you build your pack right and use quality cells the effects is very very low. Unbalanced comes through different internal resistance of the cells and how you weld/solder them together and which materials you use for it. If you use nickle for your serial connections instead of copper wire that could be a reason.

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Unfortunately you said this

Maybe your words lead us to don’t understand it right. There are bms which don’t balance, that’s totally right, but even the cheap ones we use from bestech like the d140 have a balance function. So it’s not correct to say that all the bms WE use in our packs don’t balance. If you would say, all the cheap bms YOU used in your packs didn’t balance that would be a different story :stuck_out_tongue_winking_eye:

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Never said that! what s a good quality BMS to you? The ones that work as expected

Read the words I linked in my last comment, you literally said WE :sweat_smile: Good quality bms you can find here http://www.bestechpower.com/11s12s13spcmbmspcbforli-ionli-polymerbatterypack/

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:thinking:Looking good

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I’m PRETTY sure I get what @SkateYS is trying to say here about balance charging.

The vast majority of BMS’s I’ve seen here do not balance cells throughout the complete charge and discharge cycle. They will only burn off some charge once the cells reach their max voltage. If the cells ever become unbalanced, they will be balanced once the pack reaches a near full charge again.

Our BMS’s DO: -protect the pack from overdischarge -protect the pack from overcharge -balance cells once they reach 4.15V (varies between brand / model) -protect from getting too hot (only applies to temp sensor models)

Our BMS’s do NOT: -equalize cells when charging or discharging between 0% and 95% capacity

The more advanced models that he is talking about have an actual IC that will constantly monitor cell voltages and CONTINUOUSLY keep the cells balanced, even when the pack is disconnected. I know the diebms monitors cell voltage, but I’m unsure if it uses a traditional analog balance board to balance cells. These models are much safer than traditional BMS’s, as they prevent user error.

The user error I’m talking about is referring to this scenario. If you want to extend your cell cycle lifetime, you can keep your cells between 30% and 80%. Doing this with vesc settings via minimum voltage cutoff, and with a lower voltage charger is a BAD idea. Your BMS will NOT balance your cells unless you have a BMS that is configured to charge cells to a LOWER voltage than 4.2V.

That’s why these more advanced BMS’s are safer. But I haven’t seen one in a typical hobbyist use. I plan on using one for my next build.

If I got anything wrong lmk.

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I think the upcoming smart bms are the future. You can set your balance voltage and monitor the individual cell/p pack voltage when ever it is needed.

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My thoughts on topic.

1c is a full charge from empty in 1 hour. 2c is 30min etc. What we are doing is high amp pulse charge for a few seconds. Its a completely different scenario so you can’t use the 1c amp rating and apply it to a pulse rating.

As far as I’m aware there is no scientific research on this use case and it’s effect on battery life. If there is please share?

It’s logical that a battery can take a much higher pulse then it’s rated 1C charge in amps. How that affects it’s life we don’t really know.

Most people will choose shorter battery life over a high speed crash though.

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Anyone knows why my e-sk8 (Just finished building) goes full throttle when I turn off the remote? rocking a dual FOCbox, split PPM

Your fail safe is not adjusted.

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:thinking::face_with_raised_eyebrow:

Figure this one out with 5 minutes of reading. :sunglasses:

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Seriously? :joy:

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Couldn’t help myself my friend. Good luck!

No matter what we think, we are always wrong, and most of time it doesn’t take a second to realize it. That’s the world we live in. nice post!

Mate we are all noobs. This is a brand new industry. We are just varying degrees of noobs. There is always something to learn. Thats what makes it so exciting!

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