6S LiFePo4 - BMS and Charger Advise

Hello everyone,

Did not find many who tried that so I thought I would ask here (tell me the truth but please go easy on me, it is my first build), As the topic suggests I want to use a 6S LiFePo4 with a 190kv motor setup (is that too low of a voltage? Is that too low of a kv motor?) for my DIY board (which I laminated myself) and I want to have the ability to charge it using a BMS.

#BMS I am trying to buy one on Bestech Power via e-mails but I am not sure this is how I should do it, their site offers no cart! I was specifically looking at this item: Battery Protection Circuit Module (PCM) for 19.2V 6 cells in series LiFePO4 Battery Packs http://www.bestechpower.com/192v6spcmbmspcbforlifepo4batterypack/PCB-D092.html By the way, BatterySupports do not even have any 6S LiFePo4 BMS :frowning: whaaaat? I need to add, that I intend to use the BMS for charging only and bypass the BMS for the load. I also understood that I need it to have balanced charging functionality. Since I am not sure if 6S is enough, I have a spare 3S battery (LiFePo4 of course, so it will fit the others) that means I would need a 9S BMS if I do decide to go that way. I do not suppose there is a way to use 9S BMS as a 6S BMS right?

#Charger Also, I cannot find any LiFePo4 6S charger in any store that has international delivery. Can anyone suggest anything please? Is it important to have a specific LiFePo4 charger, or can I use, say, 6S LiPo charger instead? Its all about the voltage here right? Same question here, for 9S I will need another charger right? Can’t go with a 9S charger and use, say, a voltage divider, right?

Thank you all!

1 Like
  1. you want at least 24V to run your board - go with a 9s LiFePo or 6s Li-ion
  2. Forget about the charger - use a BMS, but it is tough to find LiFePo BMS’s
  3. If you want a great battery from the start, get one from @barajabali. Yes, it costs more. Yes, it is worth it.
1 Like

You’ve sent an email to the sales dept at Bestech. Now in a couple days they will contact you to initiate your order. They will email you a spec sheet for approval, then you accept the settings or request any changes. Some settings are adjustable at the factory. They will also send you an invoice. You will send payment through Paypal.

1 Like

Correct, the bms has to match the cell count. or it will not work.

They did reply! They seem professional from first look, and if I can pay with PayPal then that is great!

If I will change the motor to 245KV instead of 190KV will I be able to use my 6S LiFePo4 battery? I am in contact with Bestech Power who seem to have what I need 6S and 9S BMSes.

Since you said a 9S would be better for me, can anyone confirm that this will be OK as a charging BMS: http://www.bestechpower.com/288v9spcmbmspcbforlifepo4batterypack/BMS-D239.html

I already have the batteries but I will consider @barajabali the next time I will need to buy batteries, thanks!

Right… Thanks for the confirmation! I do not know why I did not post here before…

I would see if they have one with higher amp capability. 8a is very low. It would be much better to get one you can discharge through and have short protection along with over current and over discharge protection.

I highly recommend this one for charge and discharge. It is the lifepo4 version of what I’ve been using and it has a built in E-switch This is the best possible option for you. 80a continuous 240a peak discharge 20a charge. http://www.bestechpower.com/288v9spcmbmspcbforlifepo4batterypack/PCB-D223V1.html

This looks really good, how important it is to have the discharge go through the BMS, I see a lot of builders choosing to bypass the BMS on discharging

Charge only is compromise. Charge and discharge is no compromise Charge only is minimum protection Charge and discharge is much more protection Charge only is ok Charge and discharge is best. Plus, If you get a charge only BMS, you will also need a HV E-switch that cost up to $60 + shipping The price of this BMS is $50 + shipping

My opinion is that you should never skimp on batteries, electronics or motors.

OMG, they want me to buy two of them because “They are not made by SMT”… Any ideas, what I can do to make them sell me just one piece? Maybe other suggestions for something that is made by SMT? whatever that means…


SMT surface mount technology Every order at Bestech is a custom order because they give you options in the specifications that are very important and no other BMS maker gives you that. So their min order is 2. So you buy 2 and save one for a backup or a future build or sell it on the forum. Or you buy a battery supports with no options and then spend the additional $60 for an external e-switch that you will need since battery supports is a bare bones BMS.

:slight_smile: Thank you man.

This is what I will buy, can you confirm that it is OK please? http://bestechpower.com/192v6spcmbmspcbforlifepo4batterypack/BMS-D223V1.html http://www.bestechpower.com/288v9spcmbmspcbforlifepo4batterypack/PCB-D223V1.html

They are both what you suggested, just that one is for 6S and one is for 9S, both are for LiFePo4

Thanks again!

Those are the ones. When they send you a spec sheet for approval, you need to request your custom settings. If you need help with that. I will help you later when I get home from work