Group Buy Bestech BMS 80A E-Switch & Charge only -finished

The singel 8s bms

yes it is 10chr

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Hmm i dont know if you guys had this discussion before but there is that thing where the balancing function isnā€™t working if you do not charge the pack fully since charging is made at the end of the charge?

So if the bms limit is 4.15 does it still do the thing?

This interest me too, since all the research I have done is that the cells should be charged to 4.2V, but since you guys have been longer in this board I just assumed you knew something more than I did.

Yeah besides then the charger wouldnā€™t ever turn green because the bms wouldnā€™t accept more voltage than 4.15? So you could never see when itā€™s done charging if Iā€™m not wrong

Per cell So if your cell is at 3v it will charge only up to 4.15percell Waiting on reply from bestech about balancing

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Correct me if Iā€™m wrong, but the overcharge release voltage is not the same as regular charging voltage right? The overcharge detection looks to be set at 4.3 so you can still charge to 4.2 normally.

@Namasaki knows this shit

If the charger only outputs 42v then it can only charge the battery to 42v because voltage is pressure and current is flow. Once the pressure inside the battery reaches the pressure in the charger, it stops the flow of electrons from the charger to the battery.

The thing that you have to be concerned about is Regen braking. Because regen braking produces higher voltage and will continue to charge your battery to 43v before the bms stops the flow to the battery and then only if you are discharging through the bms.

Yup, sounds as much as I understand it. Is the bms able to disappate the energy during braking if overcharge protection is enabled? I think I saw someone mention it, not sure from where.

I have tested the theory by braking downhill on a full battery while monitoring battery voltage. Once my battery reached my bmsā€™s over charge detection value of 4.28 per cell the voltage of my battery stopped increasing. Then once I reached the bottom of the hill and got off the brakes, my battery voltage quickly came back down to 4.2v per cell. It seems that the bms is dissipating the excess current into heat. I conducted this test several times on a steep but relatively short hill. The only concern that I would have is that if this was done on a very long downhill decent, that the bms might overheat and shutdown.

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Are there still two spots left, as the title suggests?

One guy is not sure so if he backs out you can join Will change title later

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ā€œThe balancing will begin when one cell has has hit one of the voltagesā€

Whom did you refer by this?

Bestech forgot to mention

If you referred to me, Iā€™m in. Itā€™s just that Iā€™m checking the forum every other day.

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So the overcharge V will be set to 4.15V? Is this a safe bet or would be 4.2V better because of the issue which may occur with chargers LEDs which do not become green when fully charged? I just wanted to know before you place the orders with the manufacturer!

Iā€™d be interested in a few 12s if there is any space available. Ideally Iā€™d like 4, but will take whatever is available.

One space left, who ever pays first its theirs!

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