BMS locks down my Shark Pack Battery all the time

[Menace8012]

Hey hoping someone can help me with an issue I'm having with my battery. It's a 52v 13.5ah "Shark Pack" from Luna Cycle and it cut off the other day mid ride when my battery meter still read half full. When I pedaled home the battery wouldn't take a charge and my charger acted as if the battery was full or not connected. I contacted Luna and they said the pack's BMS sometime's locks down the system due to a sparking event. They sent me an adapter for the charger that was able to jump the system out of it's lock down state and take charge and power up my system. However, when I took my bike out for a ride the BMS would lock up again whenever I hit a decent bump. I've been dealing with a pretty significant rattle in my pack and have taken multiple steps to reduce vibration around the pack, but there is still a significant rattle INSIDE the pack itself as it seem the cells have some wiggle room within the outer casing. I'm guessing something has worked loose internally in the pack, and my next step is going to be taking the pack apart for a look inside, but I thought I'd see if anyone has experienced anything similar or had any advice. After multiple attempts at getting it working the pack now locks down he second I connect it to it's cradle. Super frustrating. LOVE my e-bike and need to get back out there. Cheers!

 

[amberwolf]

Unless you can send it back to Luna for repair, then you'll have to open it up and find out what's broken off or come loose inside, and fix that, and see if it continues to have a problem or not.

If whatever is rattling around is actually causing a short across cells, you could have a serious fire without any warning.


As for the cause of the failure, it could be a manufacturing defect, or it could have had some serious impact in shipping or handling, or it might be being shaken too much during riding.

 

[RageNR]

That thing sounds dangerous. As others have suggested on here with lithium batteries, it would be good to put it somewhere safe.
Disconnect if from the bike and put it in a place that wont catch your house on fire, in case it decides to go nuclear.

 

[Noamsal]

sounds like a loose connection in your pack, or maybe a bad fuse holder that makes sparks...
if you have warranty, send it to luna

 

[t3sla]

Shark pack is inanely difficult assemble internally, wiring management is non existent sometimes when you close the case wires might pinch or be under pressure and fail easily.

 

[Menace8012]

I finally decided to take that pack apart and the problem appears to be that the multi-pin connector from the battery to the BMS had worked itself loose over time from the rattling/vibration I was experiencing. I firmly reconnected the pins, and added some padding around the cells fashioned from some old fabric. Everything seems to be working great now - 50 or so miles in with no BMS lock-downs. I am a little weary of a spark igniting the padding so am looking into better battery insulation. It looks like they sell insulation sleeves for car batteries that I think would work well.

Take-aways seem to be to pad your pack and take whatever steps you can to reduce vibration and rattle around your battery.

 

[dogman dan]

To clarify, the problem was the pack rattled inside the case. That is bad. Really bad.

 

[Ykick]

Safe to say battery packs should never "rattle" internally. Sure, mounting bracket is one thing but deep inside the battery pack? As learned here best dig in and figure out what's going on and how to stabilize it.