Where can I get a good BMS?

Yes, you can use it with a laptop style charger. You just solder some leads to a charge port.

@oriol360 The thing with that site is the 22.2v bms only goes up to 60amp continuous.He can supply much more than that and it would be a waste for the bms to think thatā€™s the max he can do.

lets say for a moment that you were able to discharge your 8000mah battery at 100A continuous your battery would be dead in 4 mins.

I donā€™t think anyone requires 100A continuous

yea i agree. i bought a watt meter and ill update this thread with my actual amp drainage.

Good idea. You would never use 100 amps continuous but if you were climbing a hill or going 35mph you could get up to 80 amps according to @chaka

And you can supply that much so why not.

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@barajabali I have a few 6s bms modules, If you need one let me know and I will get you the specs. They are all from bestech.

This really depends on the motor you are using. larger motors will draw more current while accelerating and could pop the overcurrent while a smaller motor would not.

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I think the main word here is continuous. Sure a short burst of high current every now and then but to continually draw 100A?

Correct me if im wrong but doesnt the space cell have a 30A fuse? Im not arguing, i just think most average consumers wont need that sort of current.

Not really worth arguing over that since you are not likely to find many bms modules rated for 100 amp continuous. But you want to have enough headroom so you donā€™t lose power crossing an intersection.

@longhairedboy After ordering it took about 4 weeks for delivery. I also ordered during holiday time so that might be why it took so long. It does allow charging through a laptop charger.

I use a 6S battery with a VESC. Iā€™ve never hit 60amps. However, I live in Florida so there are no hills and iā€™ve only gone up to 30mph.

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For lipo or lifepo? Can I buy one off you

If you are located in the US I can get you one. If you are abroad it might be better for you to buy direct from bestech.

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Iā€™m in the US. Chicagoland area.

Are they lipo bms? Or lithium iron phosphate

They are li-ion, 4.2V to 3V

Iā€™m also looking for a BMS for 2x 5s LiPo batteries making one 10s battery in series. Using a 10s BMS is it simple to get the balancing wires and so on sorted since I guess you need to merge these somehow?

Also when you say buying directly from Bestech, I have checked their site out but they donā€™t seem to have a web shop and the highest rated BMS I can find seems to be 25A continuous.

It would be amazing if you could help clear these things up.

Edit: This one: http://www.batterysupports.com/36v-37v-42v-10s-45a-10x-36v-lithium-ion-lipolymer-battery-bms-p-266.html

would cost 44 USD with shipping to Sweden, it should do what I want fine, right?

25 amps continuous is about 900 watts, good to about 30 mph. The peak amperage on these things is much higher. There is a lot of information out there on how the balance connectors should be connected. If you run an image search you will get some good diagrams. I would research this until you fully understand how it all works before you begin.

And to clear up any confusion, I do not recommend using a bms on Li-po packs. You really want to have many layers of protection against overdischarge and li-po cells donā€™t have any internal fusing. You could add cell level fusing if you have the skill/time to do it but it can be a painful process if you are not geared up for it.

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Wouldnā€™t adding a BMS between batteries and VESC just give me another layer of protection against discharging the batteries too much since the VESC has a cut off too or does the BMS remove the VESCā€™s ability to sense whatā€™s going on?

Individually you would be wiring the cells in parallel and then series. Without cell level fusing a faulty cell can take a whole string of cells with or without a bms. If this is going on inside an enclosure you will be unaware and it could end up catching fire. This is one of the reasons 18650 cells are internally fused.

Hey guys I have ordered 8 zippy 5s 5000mah batteries I plan to run them in 2 series with 4 of the sets in parallel meaning 4 10s 5000 mah batteries adding to 20 000 mah. Do I NEED a bms or can I get away without one if using xt90 connectors to hook them up and unplug for singular charging. I will be running them with 2 focbox and 2 190kv sk3s

Another question Iā€™ve decided to run with 4 motors and 4 vesc to add torque to my build in low end without sacrificing top end speeds, any ideas how to wire the 4 vescs to on reciever?