Do You Maintain *CRAP* NiCD/NiMH Cells?

[MidnightDistortions]

I got some interesting results from my 1999 Rayovac NiMH batteries. First off, i barely got much more than 15mAh out of one of them from doing a discharge in this remote i got set up. I discharged them until they were basically under 0.1volt and managed to get 15mAh from that. Did it again a second time and the battery got weak and lost the mAh. So it's definitely not a good idea to repeat fully discharge extremely old NiMHs that do not carry much or any mA. The interesting thing is that battery reaches 1.5 volts on recharging. The other ones don't reach that so im going to discharge the other 2 in the remote, recharge them to full and test them for capacity. Im going to try only discharging them to 0.9volts which is the safer course of action and see with a few refreshes whether they can retain mA.

 

[SaraAB87]

I have finally decided to recycle my Duracell 2650's as they are quickly losing capacity and will eventually die, crap cells anyways is what most people say about them. Oh well I got them for free so I don't care.

 

[MidnightDistortions]

One of my 2300 Duracell batteries went high resistance and is showing 20-30% capacity and can't be used in any of my flashlights. Threw it in a weather radio clock along with the other 2300 Duracells. The Rayovac cells does not show any capacity but works fine in tv remotes. My 2500 Energizers continue to degrade but amazingly still shows over 950mAh in capacity so it runs fine in a daily use flashlight i carry around the house, pretty soon though they will be used as backup tv remote batteries or PC mouse.

 

[MidnightDistortions]

It's interesting to note that my 2500mAh Energizer cells actually jumped in capacity!! Some of them as high as a 10% increase. I have played around with crap NiMH cells to notice they don't really regain capacity over time but these cells did and not just one but all 4 cells did this. I kinda experimented with this because it seems they only degrade if they are not slightly overcharged into my Duracell CEF14N charger. It could only stand to reason that the Energizers suffer from high resistance and will not fully charge in the La Crosse (BC1000) charger.

I wonder if WalkIntoTheLight can confirm, this since WITL is the only user on here that plays around and uses crap cells. I won't hold my breath though that these batteries are getting better, they still self discharge within several days so i generally will recharge them every other day to just put back what charge was lost. It might also be the reason for the jump in capacity.

 

[MidnightDistortions]

Active
La Crosse BC-1000 (current/main use charger for all NiMhs/NiCad cells)
4AA/2AA Duracell CEF14N (use as backup, crap cells only)
4AA/AAA Energizer charger (emergency charger, crap cells only)

Inactive/Dead Chargers
Eveready NiCad Charger
2 Rayovac NiMH Chargers

AA's around 1000mAh (or higher) usable capacity (best batteries are on top)
4 2600mAh LaCrosse (2014)
4 2300mAh Duracells (2005)
3 1800mAh Duracells (2005)
4 2500mAh Energizer (2005)

2AA Eveready NiCad (1997 or earlier?) (200-300mAh capacity)
3AA Rayovac NiMHs (1999) (no to very little mAh capacity only works in remotes or clocks)

4AAA La Crosse (2014)
7AAA Energizers (2006)
4AAA from a Cobra walkie (2007) (360mAh average capacity)

I had no idea the Duracells were sort of bad until i cycled them in a charger and tried using them in a USB charger for cellphones, though they work just fine in flashlights, portable cd players and radios that take AA batteries. The LaCrosse batteries were just terrible from the start and had them overheat a few times in the charger on negative side of the terminal (they might have been severely overdischarged). I was shocked that the Rayovacs even hold a charge but doesn't give out much mA. Usually i'll just continually topping these batteries off, the Duracells maintain their charge for longer than any of the others (up to 3 months!) so they don't require charging as much unless i drain them. The Energizers require charging frequently (the self discharge is really high), but they perform decent enough to be put in a flashlight after being left on the charger, trickle charging for a day. I didn't add the AAA's i got with the LaCrosse charger only because i never ran capacity tests on them but they performed fairly well for AAA's in the USB charger. The Rayovac and Eveready are good enough for tv remotes. I haven't needed to recycle rechargeables yet but if any of these batteries start requiring a charge every few hours or start expanding or something to that effect i'm going to permanently retire those batteries.

Wanted to give an update on my crap cells. Most of them seem to be doing fairly well, The 2500mAh Energizers won't hold a charge for long and they are close to being the Rayovac cells. The Nicads no longer hold much of any capacity and a few of the Energizers are showing HIGH in my C9000 charger. A few of my Duracells went bad and they self discharge too quickly. With using the remaining power in my alkalines in this pest device that originally needed a 9V but i hooked up an 8 battery pack up to it and it has been running quite well (well with some older alkalines leaking all over, but it's not surprising). The Rayovacs do quite well in clocks, at least the digital ones. Tried using an analog one but there's really no milliamps in those cells so about the only thing they can power is remotes or digital clocks. They will be replacing the alkalines in any clocks that i have currently along with the duracells that are going bad. The 2500mAh Energizers i will experiment in clocks to see how well they function. Some of the crap cells have gone in a LED strip and they have been fairing quite well so long as i keep an eye on the voltages so none of the cells reverse charge and they'll most likely end up like the Energizer AAs.

Trying to hold onto the AAA cells longer than the AA's since i had already bought AA cells in 2013-2014 and want to wait before getting a 12 pack of Eneloops. I do have an 8 pack of Eneloop Pro AAA cells and a set of AAA radioshack cells so those cells will tide over if the AAA cells decide to die out. Already the Energizers and even La Crosse batteries won't function well in this laser pointer without topping the cells off, give it a week or so and the laser will dim out, not the case though with LSD cells but i'm going to try to hold out until 2017-2019 for some regular AAA Eneloops to try to space out the lifespan of the cells.