I have a 10s4p battery pack that is^h^h was mounted under my deck with 3M Dual Lock tape. I then had screwed a plastic enclosure around it, made from a plastic drawer organizer.
Well, it all fell apart. As best I can figure, after a ride on some cracky asphalt or a few too many bumps, the Dual Lock gave way and the battery dropped. The battery hitting the enclosure was enough that it cracked and it all ended up on the ground.
How do you experts affix your batteries to your deck? I’m considering something more aggressive like a metal strap.
Careful with metal, if it shorts across the p-packs you’re in for a world of trouble, make sure there are no sharp edges and the metal is WELL insulated
I think the standard is using some heavy duty Velcro to hold the battery up and filling the space around with foam to hold it against the Velcro, also stronger enclosures that won’t crack under stress
Thinking of buying an smart BMS for my 12s3p setup.
Does the discharge rate matter? If the discharge rating is 20A, does it mean that BMS is able to drain the batteries at 20A? If yes, how can such a small board handle this and where would the heat go?
Do I need more than 20A for charging ? Even If I charge at 1C, I would only need 9A for my 12s3p.
Thank you, I understand. After inspection, the enclosure failed because it was only attached to the deck at 4 points, and they were weak. I’ll re-do the enclosure with a full-length flange for screws, instead of 4 tabs. I’ve also increased the amount of 3M Dual Lock holding the battery up.
I like the idea of some foam to give the battery a little extra support. It would reduce the amount of shock load on the enclosure if the battery were to come loose.
The current rating is the amount that can pass through the BMS, not the amount the BMS can dissipate on its own. Most BMSs can dissipate between 20 and 200 milliamps per cell.
If you want to use your BMS for discharge, then the current rating of your BMS should match the maximum discharge capability of your battery. For a 12s3p of (I’m assuming) 30Q cells, that would be 60A.
If they are 12AWG or bigger and silicone-insulated, they should not get hot enough to damage it, no. However you don’t want those rubbing together under vibration so you should put fishpaper between them
For your setup running 12 gauge wires shouldn’t be big a problem. They might get toasty after climbing some hills but should be good. If they get too hot, like that you can’t hold your fingers on them, then it’s time to change them to 10 awg. One other restriction/problem could be the connector. From what I see that looks like an XT-60 and aren’t rated for high amps. Consider using Xt-90 for your main connection such as from the Vesc to batteries
The limiting factor on what the max wire gauge is being able to get it in between the BMS layers, currently it’s the only way I’m getting everything to fit right…hurting for space as always. I think I can get 13awg to go through the e-switch but probably not 12 and definitely not 10
Do the Unity wires and connectors usually get hot?
I’m building a 12S3P 18650 pack for a dual motor(6355-190kv) setup. I can buy LG HG2 for $3.5/cell. Samsung 30Q is a little cheaper but it provides 5A less than HG2. Which one should I get?
I’m planning to install both motors on the back. Would you guys recommend installing one on front and one on back ?
You mean dual diagonal? Its only real benefit is extreme traction in snow, rain, et cetera. (You still have one wheel on each truck steering even if the drive wheels are skidding) Also sometimes it allows you to use narrow trucks with huge motors. Sometimes it means you will have torquesteer though.
