I’m a newbie and need some advice about some rechargeable batteries that I am considering purchasing. I’ve gone through this forum trying to find some answers but haven’t found what I need.
The batteries are AA NiMH Energizer 2450maH that have been put together to make a 12-volt pack. The tin strips are spot-welded and the batteries are glued together and wrapped with clear plastic. They were designed for medical devices and were never used or charged. I’m sure that when they were manufactured they had a charge - but now when I took them apart and tested them, they show .007 volts. I’m unsure about their age. I’m concerned that these batteries have discharged too much to be of use. I have heard that AA’s should never be discharged below .1 volt or they will be ruined. Does that apply to a gradual discharge from storage?
I have charged 4 of the batteries and they each charged to 1.327 volts. I am running some tests on these to determine what their longevity is.
My question is whether I should pursue this or run away? Are there any tests that you would recommend that I do to determine their suitability?
They have been basically discharged to zero, there is not any real extra risk from using them, they will have lost some of their life, instead of 500 recharges you may only get 400 (not sure the exact numbers for that model) but otherwise they should work fine.
Also those batteries don’t hold a charge for very long, you may find after a few uses (or even now) after you fully charge them they empty themselves in a week or two. This is normal for that model, i used to have some, you can get low self discharge NiMH batteries today, the best are called eneloop but if you got these for free then go ahead and enjoy them.
Not sure what quantities you are planning on purchasing or what your "reselling" entails but I'd be wary of Energisers.
I have read quite a few "anecdotal" threads here and at CPF suggesting that there were some really bad batches of Energisers over the years.
It's one thing to take a chance on a small number for yourself but do you really want to be dealing with unhappy customers if they turn out to be crappy cells?
Ok - that’s good to know. I was looking at around 800 units and reselling through Amazon FBA. Originally I thought I would do the separation myself - but have quickly realized that’s not a good idea. Was looking at selling them for around $10. The last thing I want is a bunch of returns because people are dissatisfied. So…probably have to put a stake through the heart of this idea.
Imagine you charge it and in a week its dead, sometimes faster, sometimes a bit longer
Someone puts it in their remote and thinks the remote is busted a week later, someone charges it and a few days later uses them for a toy car and they last a few minutes, they are charged and put in a flashlight and are dead when you need light, believe me those batteries are a royal PITA
They are only useful if you can time the charging to the same day that you need to use them, after having to do that a few times i gave up on them
Also most people have 6 or 8 hour chargers so using them the same day is not often doable
At the time they came out you could get these or alkaline, so these were actually an improvement, and for the first few months when they were new they kept a charge for a month, but as they got a few dozen cycles and a year of age they just settled to high self discharge. Compared to alkaline a few dozen cycles is great. Once low self discharge came out these were destined for the dustbin.
Makes sense. So they aren’t really defective - just old technology. I had looked up the spec sheets and didn’t see a lot of difference between the 2450mAh and the current 2300mAh. The discharge rates seemed similar - but that’s under use, not idle. The last thing I want is batteries that aren’t ready when you need them.
Actually that explains a lot. My wife had purchased some clearance rechargeables for use at her work and she was complaining that they didn’t seem to be working right. I think they may be discharging too quickly.
Some older Energizers weren’t bad, some weren’t good. These are old. Not used for that long (likely years) is close to abuse. They would probably (mostly) work and likely be kind of a disappointment. OK to mess with yourself but likely a poor business endeavor.
I actually keep a few older NiMH, if i want to toss them in something that has massive high current draw or loan to someone where i will never see it again then they are used. I have some old energizers, rayovacs, duracells, they are not used much but since i already have them i can loan them out and if they never come back i’m not bothered.
While recycling batteries recently, I found a battery case with 4 AAs in it which turned out to be red label Tronics (2000mAH). Two were zero volts and wouldn’t charge at all but two with a bit of patient charge/recharge came up to 900 and 1500mAh. Not spectacular but still good enough for light duties - the high self disch. could be the biggest problem with these.
So if the cells are useful to you then don’t worry that they haven’t retained 80% of their original capacity - if you can use them then put them to use!
Middle of the road advice ..Buy some and try some . My guess is they won't impress you if you use eneloops ....and your wifes issues may just be an item that wants higher initial voltages. I'd take her batteries and run lights with them ....or a remote control :P
At ten cents you aren't risking anything .. the greater risk is probably not trying them .Buy some ...and make a decision
i would cycle a pack on the triton and get a baseline.
then leave a fully charged pack sit a month.
discharge and see what they have left.
not sure if you have a hobby charger or even a c9000.
i have some 4.5 ah 5/4a packs that are 10+years old that were dead like that but new.
forgotten in hospital inventory.got like 50 of them free.damm good batteries!i rigged most up with powerpoles and sold them at hamvention to the qrp guys.
the ones i still have will run my ft-817 a long time.
so age and 0v may or may not be a killer.
The problem is some will work better then others, if he has a 20% failure rate chances are it won’t show up in a test of a couple batteries, and selling old technology thats failure prone won’t make your customers happy.
If they were old eneloops i could agree to disagree with you, i wouldn’t sell them but many people would
Batteries are funny creatures. I always assumed if a battery was below a certain point it was gone. I have a 12v car battery that tested at 2v. I put it on charge to see what would happen, and it went to 13.68v over the next 30 or so hours. A week off the charger and its still at 12.78v and holding nicely. No idea how many amps (CCA) its got though. It cant be good though.
lead acid is well understood, what you have it not a deep cycle battery so being down to 2V is virtually 100% discharged, it lost life just going down to that level (plates are sulfating) and the longer it was at that low level the greater the level of sulfation that has accumulated.
That battery depending on its age and usage could be near death right now (if you had that information it can be estimated), you can test its cranking amps at many auto stores (in Canada anyway)
Its 5 yr old and was replaced in the car I took it out of just because it was 5 yrs old. Prevention, I dont want my Mrs to go to start it and find it wont. I was using it as a swap battery between one in another car, and one on the charger. The car doesnt get used at the moment, but pulls a small amount of juice constantly so flattens a battery over a month or so. Since then the spare car has a brand new battery in it and that is permanently connected to a battery maintainer/charger so has no issues at all.
This thing is tough. It was a 520cca, I assume 9 or 11 plate maintenance free.