Looking for the DUMBEST NiMh charger of all chargers out there that never stops charging! Why? Read the OP!

Batteries and Chargers Chargers
1

I want to break-in all of my AA and AAA NiMh batteries(both new ones and months old ones, none of them have too many cycles on them so Im sure that break-in is perfect mode for all of my NiMh’s except for my six Eneloops which are couple of years old with some miles on them), I have C9000 to do this, but it takes between 1.5 and 2 days to do so on 4 batteries at a time, thats slow, really slow, so I have revised break-in cycle a bit:

During first break-in mode, I allowed C9000 to charge at 0.1C for 16 hours, then pulled them(batteries) out, reinserted them back in and discharged at 0.1C(forgot that C9000 discharges at 0.2C during break-in mode as per manual) and then pulled them out and reinserted again for yet another 16 hours 0.1C charge.

It took something like forever and my error with selecting slower discharge rate only added to it, yet after it was done, my first 4 broken-in batteries had slight capacity bump and their capacities matched those which other members here have reported on theirs(Turnigy AA).

Ive now done first 0.1C/16h charge on 2nd run of my AA’s(one run=4 batteries), removed them from charger and Im going to put them into flashlights that match 0.2C discharge rate and simply let them drain batteries empty.

As I write this my charger is already occupied with 3rd batch of AA’s on their first 0.1C/16h charge marathon, as soon as they are done, I will put the 2nd batch back in for their second, final 0.1C/16h charge.

I will repeat the same sequence with 3rd, 4th etc batches.

So after all that was said in this post Ive finally come to the point where I ask you exactly what is written in this threads title - I need simple, slow charging dumb charger to do manual ghetto break-in charging of my cells in the future!
Why? Because I have only one C9000 and would like to stay on ultra low budget to keep on breaking-in new cells in the future more efficiently, I dont need/want(not sure) another C9000 to do it :D!

This could be either one charger that charges AA@200-250mA rate and AAA@80-100mA rate or those could be two chargers(each for AA and AAA respectively) if there is no such dumb charger that will charge AA and AAA batteries infinitely at the rates described.

Thats it, I need dumb charger that never stops charging and does so at 200-250mA for AA’s and 80-100mA for AAA’s!

Bring ’em on!

(I know about 1$ USB charger that charges two AA/AAA batteries at 160mA rate, I own one, but Im not sure whether it stops charging batteries at some point or not)

2

Apparently it is not :wink:

3

My Varta Ease Energy Pocket (dumb) Charger charge AAs at 160-185 mA (not quite 0.1C for my, almost all, AAs but yeah, quite usefull, because my BC-700 doesn’t have break-in mode) and AAAs at 70-80 mA, and stop charging AAs after 16 hours and a half… something like that. Don’t remember AAAs stop timer, between 8 and 10 hours I’d say. I still use it from time to time, especially for very old batts.

4

look at these, basically u want a “overnight” 16h slow charger, they almoast never have a cutoff since its not necessary (it does not hurt the battery too much if it stays in there)
http://www.gpbatteries.com/INT/index.php?option=com_k2&view=item&layout=item&id=284&Itemid=87

5

For the most part, you are correct.

My observations seem to mirror what many others have found. With AA Eneloops, the C9000 break-in cycle has only reduced the cell capacities. With each successive break-in cycle, the cells showed less and less capacity.

I spoke with an engineer at Maha Energy about the issue and he kindly replaced the charger (under warranty) with a brand new one. At that time, I forgot to ask his opinion about the break-in cycle while using high quality NiMH cells. After receiving my new replacement C9000 and buying another new one, I noted the exact same results of diminished capacity with each successive cycle (3 C9000 chargers, 2 successive firmware versions). I did my own research and found that many had experienced the same results. I called the engineer again and asked for his personal opinion. He told me that high quality moderately cycled NiMH cells do not deliberately need to be charger cycled to maintain them, and that to do so will more often result in loss of total cell capacity. Also, a single deep discharge will very likely damage a cell.

My test Eneloops were a mixed batch of gen1 and gen 2 of various ages (brand new never used to 4 years old). I have since observed the same diminishing results with all NiMH cells that I have tested, which included Powerex 2700 AA, Maha Imedion 2400 AA LSD, La Crosse NiMH AA, Tenergy Centura AA LSD and Rayovac NiMH. The only cells that have benefited from the break-in cycle were some very old NiCad AA’s.

I have close to 100 Eneloops. All of my batteries are in a rotation, get used and then recharged approximately every 90 days. At the first sign of a depletion, they are removed and tossed into the bin.

Happy “deliberate charger induced cell-cycling” to those that wish to draw their won conclusions.

6

Wow, thats interesting!
Luckily my Eneloops have been used/abused good enough to benefit from breaking in, still in the middle of the process tho.

Yet, Turnigy batteries have benefited from breaking in, at least those, that Ive broken in recently, I get higher capacity reported on those ;)!
None of Turnigy’s that I own have ever come with advertised or higher than advertised capacity, unlike other members have reported here, thats why I chose to use break-in mode.