High Power 10s Lipo Battery Pack with BMS

Could I do something like 2 3s lipos in series with both packs having another in parallel? Am I understanding that as 6s2p?

I’m just trying to wrap my head around this for future upgrades.

Ya, that would be 6s2p and double capacity

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I don’t know if anyone straighten this up yet (I haven’t gone through all thread) but I believe this is not correct. You’re using 2s battery so serial connecting 5 of them does not make it capable of putting 5 times the current through one of them. Only the voltage goes up. Current limits stay the same.

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Each lipo is theoretically capable of 300A/600A, so he is correct.

@Jumpman I multiplied 5ah x 60c to get 300a. Some time later I learned that this formula does not equate the true current capability of Lipos. The true current capability of my battery is more like 80-90a. And that is just a guesstimate.

My bad, I mixed C with Amps. You were right. So 7P of 30Q should give similar current to what you estimate your lipo has?

Thanks for the clarification. I also don’t trust those figures, that’s why I said theoretically, but maybe I should have used a different word.

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Here is my very artistic attempt at 12S LiPo schematics. I hope it is close to right was wondering if folks can take a look and let me know where i went wrong.

list of stuff Battery (3): Gens Ace 4s 7200mah 70C Jst extension wires: NEW 12" JST 4S LIPO BALANCE LEAD EXTENSION SILICONE BMS Bestech BMS with E-switch 12s 80a Power switch: The BMS has a built-in e switch power switch use automotive switch to control it Charge port: power button for port Charger: 44.4v laptop style charger 5A for mobileand/or (CC/CV lab power supply for home…Amazon.com: KORAD KA6005D -Precision Variable Adjustable 60V, ) Anti static wrist strap- can cable 10awg 5.5 bullets 4 bullet for motor cables (as vesc 6 has 4mm) (APS 8072S)

was thinking of Photon Remote plus app so didn’t need any LCD on board…does it cover everything? if not get:

Battery voltage meter- DROK DC8-63V 12V/24V/36V/48V LCD Lead-acid Battery Capacity (amazon) Switch for voltage meter- Amazon.com: E Support 16mm 12V 3A Car Green Light Angel Eye Metal Push Button Switch Socket: Automotive

few questions: i don’t need loop key b/c i have e-switch? is there anything else folks would add for protection or a nice to have?

Thanks, Justin

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I don’t see anything wrong on the diagram. The battery orientation and balance wires all look correct to me. Great choice of batteries btw. I have the Lab Power supply you mentioned, It works really well.

Similar situation. I’m stuck at the balance wires. 2 6s setup.

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Thanks @namasaki do you agree that i don’t need any voltage meter/battery indicator if i have a remote that displays it? Or you think its a good idea to put in? Thinking photon remote will be able to display all that is necessary and app can record my data while riding. Also for the Lab power supply…dumb question here but if i have a female DC charging port (5mm x 2.1mm) in board do i just manufacture a male cable to go from lab power supply to board? thx

It has been my experience using the metr Bluetooth module and app that it does not report accurate battery voltage. I contacted the seller and app creator about this and he said that the Vesc 4.12 does not report voltage to the module correctly. My module and app usually reports voltage about one half volt higher than actual voltage. So you can use the remote to monitor but compare with a multimeter for a reference

Search some of those keywords from that post looks like plenty out there on 6s2p. Gotta sift through the garbage to find the good stuff. In my experience many of the answers are out there. If you want people to tell you how to do it answers dont come in too often. Its a friendly atmosphere but not that friendly. :love_you_gesture:

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Thanks dude. Appreciate it. Wonder if they fixed w vesc 6 will do aome research. Prob opting out of display on board less electronics soldered in less problems. Was i right on the lab charger? Just create male dc from charger to board? Or better way to do it?

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Well done @Namasaki :clap::sunglasses: Just wanted to say this is really a great thread full of information and I appreciate your support to help others (including me). And 28.6k views is truly impressive!

Keep it up!

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Yes, just make a charge cord to plug into the Power supply and your charge port. Two other points of interest. 1: use a multimeter to check the output of the Lab power supply. Just to insure the accuracy of charge voltage. 2: I have found that when charging with the power supply and the Bestech HCX-223V1 bms it works better when you follow these steps.

  1. Plug the power supply in and turn on the main power.
  2. Adjust the voltage and current on the Power supply, check it with a multimeter.
  3. Connect the charge cord from the power supply to the charge port.
  4. Turn on the output of the power supply then immediately turn on the bms. The power supply will begin in CC mode with the voltage staying just a little above the pack voltage.( this reduces battery heat during the charge process). Once the battery gets close to the set voltage, the power supply will automatically switch to CV mode and stay at set voltage while the current will steadily drop until the battery is fully charged. Note: The power supply will not shut off when the battery is fully charged but it’s output will decrease to about 50ma. At that time you simply turn off the power supply output (NOT THE POWER BUTTON) Then turn the bms off and disconnect the charge cord. Note: If you turn the bms on before the power supply, it has a tendency to confuse the power supply.

Main power button 15 PM

Output on/off. 27 PM

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Really appreciate it @Namasaki. Looking fwd to getting this thing up and running.

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I’ve actually spent about 4 hours reading various post about BMS and lipos together. Tried a couple of different ways that I thought I understood to be correct. Turns out that I’d misunderstood because my BMS started to get pretty hot for a split second. That’s what lead me to post. I’m not asking for anyone to do work for me. Thanks again for the images though

Our friend Lucy @bestech came back on the BMS I was going to order one i had found many people in forum have used before and she said that one is no longer available but she has an upgraded one. hcx-d528v1 It has e-switch as well and spec sheet seems to be ok outside the short circuit protection at 480a. Does anyone have experience with this BMS? Regardless of what i order I will most most likely have an extra one due to the min 2 order. so will post if folks are interested. hcx-d528v1

Tell her the short circuit detection is too high and needs to be lowered.