Nice to know but sounds like a lot of work, and cost, to recover an inexpensive (by comparison) pack. I bet All Battery would have replaced it for the cost of shipping.
I agree with Rick’s assessment of the pack’s construction. I think if I buy more from them I’ll buy cells and PC boards and wire up my own packs using sturdier construction.
Thanks Rick. Is it safe to say that the cold temps did not cause this to the battery pack?
So Rick, you are trying to revive a cell that did not charge? Doesn’t the fact that this cell (which I assume is in series with the others) did not charge mean it is damaged? Given the same charging current as the other cells (which must be true) the fact that it did no charge to over 0.9 volts; does that not mean it is permanently damaged?
I’m assuming “balancing” in your post means isolating this one cell for individual charging.
Just curious why you are even attempting to recover a cell that seems obviously bad.
Regards, Greg
Hi Greg & Shawn,
Yes, I have isolated the cell and balanced it first at 4.20V just like the other three. The cell is not damaged or bad, but in some cases like this extreme temperatures could have cause this one cell not to function properly. Right know the pack is at 15.7V “slowly” discharging from 16.8V at full charge to 9.6V. Once the pack has fully discharged we will run it through several cycles (charge/discharge) to make sure this one cell along with the other three are functioning properly.
Greg, the reason I’m attempting to recover this battery-pack to a restored state, is because the customer asked me to.
Shawn, my guess is that cold temperatures cause this, just make sure that if your storing your battery-packs in temperatures below 40 degrees I would take them inside for at least an hour or two before charging. When we received your battery-pack it was a little cold, from shipping in these temperatures. So, I let it sit for a day before we attemped to recover it. I can’t tell you the milliamps or what manufacturers cells these are, but it seems to be responding just fine. I’ll know in a day or so and keep you informed.
Rick Isard
Cordless Renovations, LLC
Hello everyone,
Charged & discharged Shawns battery-pack twice reaching 16.5V on the first cycle and 16.6V on the second cycle, with 2031mah of discharge. I can see nothing wrong with this pack except I recommend not storing it in cold temperatures.
Rick Isard
Cordless Renovations, LLC
Thanks Rick thats good to know it had nothing to do with the battery pack or the engines. I might end up going with a battery that can handle colder temps for my winter runnning. I have an extra critter control so I can convert a boxcar into a battery car that will hold larger batteries.
Shawn,
Sounds good, take a look at our C-10NM Battery-Powered Trailing Car…
Rick Isard
Cordless Renovations, LLC
Thanks for the info Rick, interesting that the cell did not charge, but was not damaged. Great luck for Shawn.
I’ve rarely seen this happen, i.e. a pack with a cell not charging, but the cell would come back. I’ve seen nicads for example with an internal short that could be blasted and the cell “brought back”, but never a lithium one.
Any other theories besides the two you gave, possible not balanced/matched cells, and extreme cold?
Anyway, congrats on recovering it.
Regards, Greg
Greg,
Over the past year, I’ve seen many cells from “X-Company” that were not balanced prior to manufacturing and this could have been the problem in this case. A couple of times a year we purchase our competitors products just to see their manufacturing style.
We have restored several packs for our customers over the years and this is not uncommon, especially when four cells are more than .03 Volts apart. But, cold weather can make any lithium cell unresponsive, especially when there stored in temps under 40 degrees for long periods of time. In this case once we balanced the cell with the other three ran the pack through several cycles on our analyzer and came out with the same results each time, we knew the cell was responsive and able to hand a load.
But I agree, we don’t always get these results.
Have a good evening,
Rick Isard
Cordless Renovations, LLC
Thanks for the info Rick, real world experience is always the best, theory is just a starting point.
Weird how it happened. I do the same recycling “dead” laptop battery packs, but typically 1 or 2 cells are totally bad, but the rest are fine.
I just charge the cells individually and see how they respond. I usually try 3 or more cycles to make sure the cell charges consistently.
Regards, Greg
That’s good info to know since I usually store my engines out in the unheated garage.
I keep my All-Battery Lithium-Ion powered locos and trailing cars in my unheated garage during the winter. It gets below freezing in there. No problems to date. I think this is at least the third winter they have been in use.
It may be freezing in the garage, but if the cells themselves get cold enough to freeze (and I don’t know offhand the freezing point of the electrolytes of batteries off the top of my head)… but if they do actually freeze, bad stuff happens… maybe Rick can comment on this statement.
I’ll have to look up those temps… since it does not happen here, I’ve never really researched it.
Greg
Hi Greg,
This is the LG table temperatuure conversion for their lithium-ion cells. My calculations in freezing temps were a little conservative but it’s better to be safe then have a problem.
Here’s what LG say’s; Lithium-ion cells work within these discharge temperature limits of -20°C to 60°C (-4°F to 140°F). The performance is temperature based, meaning that the rate capability at or below -20°C is reduced due to the increased impedance of the electrolyte. Discharging at low temperatures does not harm the battery and may be used down to -30°C (-22°F) with acceptable results. Larger packs will be necessary to compensate for the reduced capacity at these temperatures.
What I didn’t see and they don’t list it but storing lithium cells in cold temps for long periods of time. But I always always promote caution before charging or discharging any lithium batttery after it’s been stored in cold temps for long periods of time.
Hope this helps, gotta go get my foot operated on, bad fall on ice…
Rick Isard
Cordless Renovations, LLC
Cool, so looks like the electrolyte must freeze at a really low temperature. So basically, leaving the batteries in an unheated garage is fine, unless you live in a REALLY cold place.
So, it may be that charging is affected by cold temps.
Hope your foot comes out ok, broke it?
Greg
That’s exactly right, trying to charge a cold lithium battery-pack is usually the problem. Cold electrolytes don’t respond well when charged or discharged and I that was the problem in Shawn’s case. I always infom customers to bring their batteries inside for at least an hour or two before charging.
No surgery on the foot, but separated the joint about 3mm, tore one ligament on the right side of the ankle and stretched the left, beside a hair line bone fracture at the joint. No good. I’ll be in a boot for a long time plus no driving, right leg.
Rick
Thanks Rick. Ill have to keep the batteries inside the house and let them warm up before recharging. Good info,