Eovan Custom Battery Pack

I wanted to build a 12s4p P42A pack for the eovan super that is using Panasonic cells. Wanted to do a practice pack and 12s4p is a good size.

Cant find any pics of the inside of the pack and am tempted to open the heatshrink to see how this is made unless someone can explain via the outer cables. Where does the BMS plug in?

The battery has an XT60 connector and this 2 pin JST(i think) coming out of it.

I assume this is a possible swap as eovan said they would be releasing their own molicel pack, others have inquired about doing it but i haven’t seen anything done.

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Have you looked on youtube? There are a few pack building videos that might help.

The bms is probably in the front of the battery unless its one of those pcb ones… It’s actually soldered and/or wired accordingly. You can replace it, if, once again, its not one of those pcb ones. Those are hard to replace and requires DIY.

To make a battery, you’ll need a lot of safety tips from battery builders. Do not attempt it if you have very little knowledge on safety.

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This is all i can find that is using the same 2 pin connector that’s outside the pack. Very annoying doing this with eovans esc as i would have just used a daly BMS…

or can i still use the daly bms for the new pack and just wire the 2 cables into that JST connector so it works with the rest of the system?

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You should be able to just connect another JST pigtail or recycle the old one. And I’m guessing that JST is just connected to the main positive and negative of the pack. Connect it how you like but I dont recommend splicing into the balance lead.

Of course theres nothing stopping you from swapping both sides over to something like an EC2 or XT30. JSTs are so fiddly and fairly easy to connect backwards which would probably fry your BMS.

would this be just plug and play? I cant connect to eovans esc but im doing just the battery, are there any settings i would have to change? and if i did have to is there any way of cutting off their XLR cable and soldering just a regular usb ?

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Thats the part I dont know. First off whats an XLR cable? I do know that the specs on USB are fairly specific and go beyond just voltages since its a data communications cable as well as charging.


was told this was an XLR cable, they use it for connecting to the vesc

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I’d just stick with the XLR cable since I dont know if the two are compatible. Just out of curiosity, whats on the othe end? Does that connect VESC to a computer? If so I definitely wouldnt mess with it without hearing from someone with reputable advice.

lol yeah cant find this connector anywhere tho

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Is the XLR cable connected directly to the battery?

Are you trying to replace the jst? Or something else? Im unsure on this one since I don’t have the full picture here.

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nah its into the epoxied ESC

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And the other side plugs into?

No im just building the same 12s4p battery pack with better Molicel P42As, i see no bms just the JST so im wondering what kind of BMS is used for this type of pack

I uploaded pictures of the two wires coming out of the pack and was inquring about how the BMS would be handled


111 its this yellow plug.

u cant see the pins but its a 3 pin in a triangle shape

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Ok what does the other end connect to? A BMS or your computer? Either way it sounds like thats proprietary and you’re stuck with an XLR connector unless you buy a new BMS and or esc.

You can use any bms, either discharged or bypassed. They both will power on the board. You don’t need a specified bms. Unless the bms was programmed to only work for a specific thing, you can just use a Daly bms with no issues. All you need to know is what plug is being used to make that connection.

I can turn on the same esc with two different bms type batteries. Nothing is needed. The only difference would be the discharge rating. Bypassing ignores this part.

For this pack, you will have to open it and see if its pcb type or welded/soldered. Welded are easier to deal with.

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Sorry for the confusion this is the wire for programming the VESC, this plug doesnt touch the bms.

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Thanks, my plan was to peak inside. Didn’t wanna go in there for nothing. I’ll report back

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