Fein tool or small angle grinder. Fein is better as you can control the depth and line. Diamond blade:
https://fein.com/en_us/accessories/diamond-saw-blade-63502166210/
Anyway…
edit: fire extinguisher at the ready… lithium fires are easy to contain. don’t use water to put out the fire.
will a hot wire (like foam cutter) not work?
I don’t see that is a viable option with this material. It would release some incredibly noxious fumes, be messy, and have a higher danger factor with the batteries and wires in such close proximity.
Which one are you to? Similar to this guy?
Mine only has 1 speed and it melts the plastic and junks up the blades just like the dremel, but I am close now. I just need to (VERY carefully) do the cut across the top.
https://www.homedepot.com/p/FEIN-FMM-350QSL-Multi-Master-Top-Promo-Kit-72295270090/313327362
The real Fein tool is what I have. Expensive, but worthy every penny and I use it every day. The diamond blade better for that type of work, but standard blade should do fine.
It’s open. Here are some quick shots. I am checking things with my multimeter now. I did hit a small orange wire when I cut across top and lost patience, haha.
Very nice , thank you for the pics , so we have fuse on + , probably around 10-12A
Try to get the number on the solénoïd switch please
SCORE! All the cells are good. It is an interesting configuration, but all the channels are balanced within .01v of each other. The cells are resting at roughly 3.24v. This is quite a fancy BMS. There isn’t much room to get to it due to my choice in cutting across the top. I am not sure yet if I would cut it the same way again or not next time.
I would say more. It’s a TE Kilovac relay.
Thanks for the pictures ! You think you can get a model number, brand or whatever useful for the BMS ?
Wait you mean you have another battery pack ? 
I meant figuratively speaking, haha. I am swimming in batteries as it is.
BMS is Staff Systems LLC
Model 1030M
There is a 300amp fuse between battery and relay.
Weird, I don’t find anything on this company on the web. I mean I’ve found Staff systems, but this is certainly not the good one 
Ok I got it !
It’s Stafl systems :
1030M is certainly a custom made model coz it’s not listed on their website. Now we know a reputable company where we can buy our 14S BMS even if it’s priced 200$ it’s proven to work !
So good !
That’s a pretty big fuse 
.
If you take a closer look, each cell is connected with a part acting as a fuse wire. Which leads me to think, not only they are protecting each cell individually but also certainly the bms.
That’s a pretty nice battery we have there !
Also, what’s your opinion on the bonding method they used on top and bottom part ? Would you say it’s glued or kind of melted together ?
That USED to be a pretty nice battery until someone butchered it! haha…
@foilmore - If you can save the case, it will fit perfectly in your new board.
I found this website. But not the exact model. It may have been custom made for lift
Geez we posted it at the exact same time 
. Thanks !
Hopefully we can help lot of people now with good quality BMS !
Ha ha… I think you posted it first. I must have missed it while I was researching
300A for the fuse because they work with heat ( amp) vs time , so over rating will assure life operating
It is all in data sheet
Just like over rating a bit bms , fuses cells …
I used a 200A which go pretty warm with 140A continious
