Noob question thread! 😀 ask your questions here!

Hi! To find out what I can do, say @discobot display help.

If your not bypassing:

  1. Running the battery too low.
  2. Drawing too much current.
  3. If a P-group or Lipo pack breaks loose or otherwise disconnects from the battery.
  4. If a short occurs in the battery or anywhere in the entire circuit.
1 Like

To reset, simply push or flip the switch off and then on.

1 Like

If I lose a balance lead but not the pack, will it still cut out? If it cuts out do I coast or stop dead?

I would suggest buying quality parts from torque board as they have the kits. BKB hasn’t gotten the kits together yet but are coming soon but has the parts to make everything.

Depends on the BMS, some are more touchy than others. Either way you won’t stop dead, you’ll coast. (probably.)

BesTech 223?

I dunno, never used it. Set yourself up an experiment and see! We’ll all learn from it.

1 Like

Will report back in a few days then, still need to make half the battery and some hella nasty adapters

1 Like

I can tell you that if the BMS fully disconnects the battery, you will lose brakes. Not sure if a missing balance wire will cause a full disconnection (charge and discharge), or just the discharge portion. (This is all assuming a not-bypassed BMS. If your BMS is bypassed, it won’t be able to stop you from drawing current from the battery.)

1 Like

Since I’m using a battery sled which is more susceptible to shorting I’m gonna use the discharge mode, 80A should be enough since that’s the cap on the batteries

1 Like

Thanks man I can now confirm it is the charger that has shit itself and not a simple reset of my bms. :expressionless:

Battery Mounting Help

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.

https://www.lithiumbatterypcb.com/product/13s-48v-li-ion-battery-pcb-board-54-6v-lithium-bms-with-60a-discharge-current-for-electric-motorcycle-and-e-scooter-protection-2-2-3-2-2-2-2-2/

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.

Thanks!

1 Like

I just got a roll of this stuff and its super squishy, also waterproof

1 Like

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.

1 Like

Yes, if a balance lead disconnects, the bms will go into protection mode and cut power to the vesc so you would simply coast to a stop.

1 Like

Will the phase or power wires get hot enough to damage the BMS? 80A in and 2x 65A at 12s

image image