Topic starter
Has anyone in the single track hive mind rebuilt a battery pack for their lights? I’ve got a 98ah lupine pack that has battled on for 9 years but gave up a couple of weeks ago. I’ve got myself a new battery but decided to investigate the old one. I managed to get the thing apart without too much drama and by my estimates it’s got around $200 of good quality LG 18650 cells in it. Providing it’s not the BMS that’s cooked, it looks like a reasonably simple thing to swap in some new cells. Anyone given it a go?
Posted : 15/04/2025 10:17 pm
Mtbbatteries in Lichfield will fix that for you. Owned and run by ex member Smudge on here. Although he seems to be as interested in rollerblading now as riding his Levo!
He's a great and helpful chap.
Posted : 16/04/2025 7:11 am
Mtbbatteries in Lichfield will fix that for you. Owned and run by ex member Smudge on here. Although he seems to be as interested in rollerblading now as riding his Levo!
He's a great and helpful chap.
I can confirm the above. Although not the bit about rollerblading.
Posted : 16/04/2025 7:57 am
Aren't the cells spot welded together? Last few packs I opened up were. Not sure how you DIY that. Wouldn't want to solder it.
Edit: I see there are battery spot welders on Ali Express and the like for £10 - £15. No idea if they actually work but might be worth a go. Definitely practice on some old cells first, and I'd do it outside 🙂
Posted : 16/04/2025 8:12 am
Don't bother.
A much simpler solution is available:
Check that your lights are 8.4 volts, some seem to be 4.2 volts. You might also need a stand alone charger:
Then buy some duff Makita (or similar) batteries from eBay and strip out the cells. Very rare to find that every cell is borked and you will get the best quality cells for much cheapness. You might want to add tester:
I've changed over the connectors on my lights so I can swap packs and lights around. The only item I've struggled to source is decent waterproof connectors - like Hope use.
Posted : 16/04/2025 8:31 am
retrorick reacted
Anyone given it a go?
I've done a few, some with a battery holder of the right spec to deliver the correct voltage, some soldered (i have a proper soldering iron). Also done the same for RC car batteries.
Never had any significant issues except with those batteries that require larger cables (10/12 AWG).
Posted : 16/04/2025 10:33 am
Hi John,
Firstly thanks folks for the mentions - yes, I seem to be spending more time Rollerblading now than biking! saying that, might be on it next week 🙂
Battery wise, unless you are 100% confident with what you are doing do not attempt it.
You mentioned swapping in some new cells? you cannot do this as they will have a different cycle life to the original ones and the battery will be unbalanced. To build a battery all the cells have to be from the same batch and matching voltage.
The Lupine batteries do suffer from fatigue in the cables and also corroded connectors. If you have removed the top and can see where the output lead is soldered into the output solder tabs. You could unsolder then check the output with a meter.
Pleas feel free to email me for more help, but I also noticed you put a $ sign? if in the US I would not be able to help much battery wise though.
mark at mtbbatteries dot co dot uk
Thank you - now back on the rollerblades whilst the sun is still out 🙂
But just to reiterate what I mentioned, if you are not 100% confident with what you are doing do not attempt anything, and also do NOT mix/match any cells.
Posted : 16/04/2025 5:55 pm
nickingsley and johnnystorm reacted
Topic starter
Thanks for the input guys, yes, firstly I’m in Aus but frequently travel back to the uk to see family. On balance, I don’t think I’ll attempt as it could be the bms that’s cooked. @smidge I will come and look you up when I’m over next year - I pulled the pack apart and didn’t see any obvious corrosion and shorts. I will put a multimeter across the cells though to see if there is generally any charge in the pack as this will be a pointer if there is any bms issues. Thanks!
Posted : 16/04/2025 10:11 pm
No Problem John,
As a guide, each string should have the same voltage, if they are different voltages then the battery is inbalanced and causing the problem and not much can be done to fix. The cells being LG are good quality and problems only usually occur if the battery has been left in a state of uncharge for a long period, also bear in mind the age of the battery (9 years) and the cycle life it may have had.
I would definitely check the lead and connector as a priority though. If you want any more instructions feel free to email me and I can give a better idea of what and how to test.
Posted : 17/04/2025 9:13 am
