Hello guys im thinking to buy 40 batteries Samsung INR18650-25R 2500mAh - 20A and im looking for a bms any idea if this one is any good or should i use another ( im in europe so would be nice if i could find something around here)
If you are going to build a 10s4p with those batteries you need atleast a bms that can handle 80A current, unless you bypass it for charging only which i wouldnt recommend.
The word on the street is that 25R’s are not the best choice available now.
30Q’s are suppose to be much better.
And as @Tobi stated, you should get a bms with higher amp capability than the one you listed.
The reason is that these bms’s are designed to protect the battery during charge and discharge cycles.
And although some people will bypass the discharge protection either to save money or space, it is much better to have the full protection that the bms offers.
And it is a good rule of thumb to always build with supply being greater than demand. Also know as “headroom”
Your battery and bms should be capable of more than what the motor and controller will need.
Not trying to hijack the thread, but maybe the answer to this question would be helpful to @bloop too. Can that BMS do regenerative braking if the VESC is set up to do it?
I have a shipment of BMS units on the way from Bestech. All the units is with a built in e-switch, so you do not have to buy an additional power switch. The BMS units will have eother 60a (for Samsung 25r or similar in 10s3p config) discharge or 80a (for Samsung 25r or similar in 10s4p config).
The Samsung 25r cells is pretty cheap on nkon.nl (the go to battery webshop in EU). They are so cheap that I would not even consider choosing other cells because they are about double the price!
I have been using the 25r’s a lot, I am very happy with them. Sure, you can get something that perfoms better, but I dont think that you get more value for money than with the 25r cells.
I understant now and now i see … i did not consider i need to use that for discharge too (but i dont want to bypass) so ill look for something with more amps.
As @markyoe asked (and i suppose is possible but i want to make sure) with the BMS on is posible to have regenerative breaking ?
And now back to the batteries… i found the 30q but they offer a little less amps than 25R but for price they are really similar so i dont know right now. With the 25R i would have 80A discharge while with 30Q would be only 60A. now im not sure how many Ams do my motor need. I have the one form enertion tho.
Anyone could help with that? which one is better and worth buying?
From nkon.nl these batteries is very good for the price! I just ordered a bu ch of them too.
As I remember, the Samsung 25r has a slighty better discharge curve - but hey! It is a great deal!
Wich one would be better and why ? Also how do i connect them ? the one from batterysupports i saw it has 3 pads P N and B but for bestechpower i couldnt find any instructions ?
It depends on the label of your charger.
36v is the nominal voltage of a 10s pack which would be 42v.
You can look for 10s charger which charge till 42v but labeled for 36v