I just did the same fix for somebody on one of these packs - with the same problem - 1 dead string, which I replaced as I had some more of the same cells. Not a perfect match however as the new string ended up out by about 50mV. Not the end of the world but I'm working out a way of matching such groups more closely in a cell carrier connected by wires before I weld them into the pack.
I use a battery balancing machine - linked in a video I did on it! That would bring them right into balance (automatically) Well done for having spare cells, I don't stock these no name cells...
@@EbikeRepairs Thanks, I'll take a look. I have the NEEY 4A active balancer but I find that unless the strings are closely-matched in capacity and IR I can balance them but they tend to drift apart in voltage over time. Just lucky with the cells, I had a 2nd faulty pack. One annoying aspect of the latter was that it contained the most solidly-welded strips I've ever encountered, such that I ended up having to leave a bit of the original nickel in place since trying to remove it all risked tearing holes in the cell bottoms!
Ouch. This battery has absolutely no cell holders to keep the cells spaced apart. Each cell is actually a metal canister, and the metal canister forms the negative connection, with the positive at the top separated by an insulator. The only thing keeping the cells from shorting together therefore is that purple heatshrink that has been added over the top of each cell. If that heatshrink ever ablates and the metal cells underneath touch, you're going to have a bad day. As in, potentially a fire. The BMS is powerless to stop that.
The blade, the rings, all ceramic right. :) I am a little perplexed by the suggestion to entirely remove that dead bank of cells as opposed to replacing the cells with new cells with approximately the same capacity? I imagine myself measuring the capacity of another bank and finding batteries that would roughly mimic that capacity. Saves replacing the BMS and charger. What have I missed?
The rings really are 🤣 lithium batteries can be super dangerous so I will only replace cells with like for like, (Samsung 25r for 25r for example) I won't ever mis match capacity, manufacturer or model as ultimately it's not safe (in my opinion) Long story short, I can't get these purple cells, I don't like them anyway, and the battery was around 3 or 4 years old so even new, identical cells would likely have fallen out of balance anyway due to having a lower IR than the existing cells... Thanks 👍
I have, but on older batteries the pack tends to go out of balance after a while, so I don't. I only change for identical cells (eg. Samsung 25r for Samsung 25r) and won't mix and match different manufacturers or models.
so i have to repair a cell group in my triangle battery looks identical to yours but my issue is how do i get the darn plastic tabbing off? Do I seriously have to tear all the nickel plates off the good cells too and take it off as one? if so thats some bs
I got the same battery same problem however it only a couple months old and only 10 charges so could i just replace the set thats bad then since its not to old???
why not just throw in some new cells?? at first rip off the nickel strips.. then try each of the cells in that group if it comes back to life (maybe just one or two dead) ... then throw in new cells for thd defective ones
The pack was too old, about 3 years, new cells wouldn't have balanced up. Also, those cells were junk to begin with, most non brand name stuff (not eve, lg, Panasonic,Sony, Samsung,molicel etc) is junk that leaks after a few years
I just did the same fix for somebody on one of these packs - with the same problem - 1 dead string, which I replaced as I had some more of the same cells. Not a perfect match however as the new string ended up out by about 50mV. Not the end of the world but I'm working out a way of matching such groups more closely in a cell carrier connected by wires before I weld them into the pack.
I use a battery balancing machine - linked in a video I did on it! That would bring them right into balance (automatically)
Well done for having spare cells, I don't stock these no name cells...
@@EbikeRepairs Thanks, I'll take a look. I have the NEEY 4A active balancer but I find that unless the strings are closely-matched in capacity and IR I can balance them but they tend to drift apart in voltage over time. Just lucky with the cells, I had a 2nd faulty pack. One annoying aspect of the latter was that it contained the most solidly-welded strips I've ever encountered, such that I ended up having to leave a bit of the original nickel in place since trying to remove it all risked tearing holes in the cell bottoms!
Ouch.
This battery has absolutely no cell holders to keep the cells spaced apart.
Each cell is actually a metal canister, and the metal canister forms the negative connection, with the positive at the top separated by an insulator.
The only thing keeping the cells from shorting together therefore is that purple heatshrink that has been added over the top of each cell.
If that heatshrink ever ablates and the metal cells underneath touch, you're going to have a bad day. As in, potentially a fire. The BMS is powerless to stop that.
I agree, not good. These UPP batteries were all recalled in the UK
cells should be at least double shinked .. even better a cell holder with some space (air cooling)
The blade, the rings, all ceramic right. :)
I am a little perplexed by the suggestion to entirely remove that dead bank of cells as opposed to replacing the cells with new cells with approximately the same capacity? I imagine myself measuring the capacity of another bank and finding batteries that would roughly mimic that capacity. Saves replacing the BMS and charger. What have I missed?
The rings really are 🤣 lithium batteries can be super dangerous so I will only replace cells with like for like, (Samsung 25r for 25r for example)
I won't ever mis match capacity, manufacturer or model as ultimately it's not safe (in my opinion)
Long story short, I can't get these purple cells, I don't like them anyway, and the battery was around 3 or 4 years old so even new, identical cells would likely have fallen out of balance anyway due to having a lower IR than the existing cells...
Thanks 👍
In practice I've found exact matching of differently-sourced strings to be really tricky. And if not closely-matched they drift over time.
great video. have you ever changed only bad cells with the same or similar characteristics. what are the results after a while, is it working well.
I have, but on older batteries the pack tends to go out of balance after a while, so I don't. I only change for identical cells (eg. Samsung 25r for Samsung 25r) and won't mix and match different manufacturers or models.
What's holding the battery together?
Super glue 😭
@@EbikeRepairs I see, thanks.
so i have to repair a cell group in my triangle battery looks identical to yours but my issue is how do i get the darn plastic tabbing off? Do I seriously have to tear all the nickel plates off the good cells too and take it off as one? if so thats some bs
I just sort of cut the tabs off sometimes and then make sure the cells are held in place properly afterwards
I got the same battery same problem however it only a couple months old and only 10 charges so could i just replace the set thats bad then since its not to old???
Yes if you have identical cells sure :)
Throw it away and don't buy that chinese crap
what is the model of your tester?
I did a video on the channel, search 'battery balancing machine'
has anyone here actually gotten there Ecells E bike yet?
Never heard of it!
why not just throw in some new cells?? at first rip off the nickel strips.. then try each of the cells in that group if it comes back to life (maybe just one or two dead) ... then throw in new cells for thd defective ones
The pack was too old, about 3 years, new cells wouldn't have balanced up. Also, those cells were junk to begin with, most non brand name stuff (not eve, lg, Panasonic,Sony, Samsung,molicel etc) is junk that leaks after a few years
bad desing for the end 14
apparently it's common that the end 14 die... interesting
You would wash your nails for the movie. No kidding.
@@maniakfps249 working hands! I touch dirty things, nails get dirty, got no time for cleaning them every 10 minutes😁😁