Eneloop Rechargeable Battery Gone Bad

[easysurfer]

battery (mini update)

There's hope yet. I've been running refresh cycles on that AAA battery that. Got the internal resistance (IR) down to the 200's (started in 500's) according to my charger's tester. Gonna run a few more refresh passes before seeing if the battery plays nice again with the Panasonic charger. Gonna see how low I can get the IR.

 

[Blueskies123]

I have done these steps too and it is all very interesting but at some point you may want to just say, something is defective about this cell and just recycle it. It may have some connection that is broken or a contaminate got in.
If you get it to work you may find that it goes bad on you just when you need it.

 

[easysurfer]

I have done these steps too and it is all very interesting but at some point you may want to just say, something is defective about this cell and just recycle it. It may have some connection that is broken or a contaminate got in.
If you get it to work you may find that it goes bad on you just when you need it.

I hear you. From a hobby standpoint, this is fun. From trying to save a few bucks, not worth the effort.

I'll see how the testing goes though, and if the battery is still usable, I've already got it marked so know if that's a bad egg in circulation or not.

 

[Jerry1]

but at some point you may want to just say, something is defective about this cell and just recycle it.

Hey Hey Hey - We're not stopping now! This battery is going to work in that Panasonic charger whether it likes it or not. If mickeyd can claim a small victory for the little guy by getting $1.30 back on the missing news paper, forcing the Panasonic charger to accept the previously rejected batter has to be considered a Huge victory - for all mankind.

 

[easysurfer]

Hey Hey Hey - We're not stopping now! This battery is going to work in that Panasonic charger whether it like it or not. If mickeyd can claim a small victory for the little guy by getting $1.30 back on the missing news paper, forcing the Panasonic charger to accept the previously rejected batter has to be considered a Huge victory - for all mankind.

So...we march forward .

 

[easysurfer]

Battery update, part 5

Looks like the moment of truth (will the refreshed battery charge on the Panasonic) may come tonight.

I've ran a series of battery refreshes to get the internal resistance (IR) down. The IR is dropping like a rock. First refresh 618 milliohms. Third refresh got down to 31.

Not sure if the Panasonic looks at IR to decide whether a battery is defective or not. But if so, then battery's demise may have been exaggerated.

Current refresh won't finish til later tonight. Then, the moment of truth.

 

[ERD50]

That is a big drop in IR. I'm a little surprised that the maH capacity actually dropped, although the delta is small enough to be measurement error (though consistently dropping).

Is the Panasonic charger capable of loading the battery, and/or testing maH capacity? If so, then they probably do check IR - it's simply a matter of measuring the battery voltage with no-load (or maybe a light load), and then with a higher load. IR can be calculated from those readings. Example with made up numbers:

V @ 100 mA = 1.35
V @ 600 mA = 1.30

IR = Delta V / delta I = .05/.5 = .1 = 100 milli-ohms

If the Panasonic doesn't do discharge, then they maybe just look at open circuit voltage, but that seems pretty crude and is probably only for a very simple charger.

-ERD50

 

[easysurfer]

Panasonic doesn't do discharge. It just detects battery, and charges. Anytime it thinks it's defective, led lights blinks rapidly.

How internally the Panasonic works, I have no clue.

 

[Texas Proud]

I am just wondering how much electricity you are wasting to try and get this battery to work.... much less the amount of time spent...

BTW, who cares about the Panasonic charger since from your posts it seems like the worst charger you have... I would chunk that and use the good chargers all the time...

 

[easysurfer]

I am just wondering how much electricity you are wasting to try and get this battery to work.... much less the amount of time spent...

BTW, who cares about the Panasonic charger since from your posts it seems like the worst charger you have... I would chunk that and use the good chargers all the time...

I'm sure folks told Columbus he was wasting lots of food and water on sailors when he moved forward .

To quote Jerry1 "Hey Hey Hey - We're not stopping now!" We are at the cusp of victory!

 

[ERD50]

I am just wondering how much electricity you are wasting to try and get this battery to work.... much less the amount of time spent...

BTW, who cares about the Panasonic charger since from your posts it seems like the worst charger you have... I would chunk that and use the good chargers all the time...

It's all about learning and curiosity. He won't get payback on the chargers, it's a geek thing (I oughta know!). Sometimes the knowledge you gain does pay off later. Sometimes, you can just use it to bore someone to death. That can come in handy sometimes.

The electricity is almost nothing. One of those batteries is about one watt-hour. So @ 10 cents per KWH, that's ~ 0.01 cents per charge. OK, these chargers aren't efficient, there will be overhead, but even if you make that 10x, it's almost nothing. Ten charges for a penny?

-ERD50

 

[easysurfer]

Battery update, The Moment of Truth

The moment of truth arrived.

Unfortunately, ended up going backwards. After the last refresh, the IR came up as 212 . Makes me wonder if I read the last reading correctly or not. I'm pretty sure read correctly..

Tried charging on the Panasonic and then on another older charger. Battery got flagged as defective both chargers.

Closest time I can to "fixing" the battery was when I recharged for about 30 mins at 1000ma with my LaCrosse. In that case, the battery charged for about 3 hours before getting kicked out.

My last try is I'm going to discharge then charge once under 1000ma with the LaCrosse then try the Panasonic. Other than that, time to wave the surrender flag .

Still happy with my new charger. Time well spent .

 

[easysurfer]

I tried my best ...

 

[ERD50]

I tried my best ...

And a noble attempt it was!

Reflecting on this a bit, while I described the internal resistance effect, this is just a simplistic model that engineers use to evaluate things as a first approximation. In a given battery design, if that IR is increasing, it is a side effect of a complex series of changes in the chemistry and materials inside that battery. There's a lot going on. Some of it might be reversible, some of it won't be.

Perhaps if you caught it earlier, the cycling could have improved things more?

-ERD50

 

[easysurfer]

And a noble attempt it was!

Reflecting on this a bit, while I described the internal resistance effect, this is just a simplistic model that engineers use to evaluate things as a first approximation. In a given battery design, if that IR is increasing, it is a side effect of a complex series of changes in the chemistry and materials inside that battery. There's a lot going on. Some of it might be reversible, some of it won't be.

Perhaps if you caught it earlier, the cycling could have improved things more?

-ERD50

Perhaps. I may never know.

Still haven't tossed the battery out. What I did was put a red mark and set aside. I'm gonna to use a battery tester to check the self-discharge every few days to see if I notice a too quick drop. Otherwise, just won't use the Panasonic to charge the battery up. This battery seems to charge in my Opus and LaCrosse chargers just fine.

 

[Jerry1]

Thanks for trying and keeping us in the know as to what you were doing. I enjoyed it and learned a bit from this thread.

 

[easysurfer]

Thanks for trying and keeping us in the know as to what you were doing. I enjoyed it and learned a bit from this thread.

You're welcome. For awhile, I really thought we'd make it to the finish line.

I enjoyed learned from this exercise too.