Battery Maintenance Question....

[Jaybird]

Hey all,

I wanted to ask a question to the fellow flashaholics about their routine battery maintenance. I know the topics regarding chargers and batteries in various threads has been stripped, analyzed, recorded, disassembled, put back together, and eaten alive already <grin>. I've done my best to try and read them all but what I've failed to really find, and what I believe lots of people might be looking for, is how should I maintain my cells on a regular basis.

Once again, I know this is an open ended debatable question but I'll explain what I have, the routine I've put together, and then I'd appreciate any comments or deviations that other people may suggest.

Currently I'm using the C9000 charger with Duraloops all around (both AA and AAA's).

From what I've gathered in various threads and from the C9000 manual... this is what I have been following (assuming starting from a new pack of AA Duraloops):

Charge 1: Break-in (1-3 times).
Charge 2-9: Regular charges (at about 1000ma)
Charge 10: Refresh & Analyze
Charge 11-19: Regular charges (at about 1000ma)
Charge 20: Refresh & Analyze
Charge 21-29: Regular charges (at about 1000ma)
Charge 30: Break-in

<rinse and repeat from charge 2 again after charge 30 depending on battery performance>

Is this a general good schedule to follow? or should there be any deviations from this? if so, what do you recommend?

I'll just add that I've developed a little Excel spreadsheet to accomodate the above schedule with inputs for Mah and voltage readings at certain intervals to keep track of the battery performance.

Thanks !

 

[sparkysko]

If I really wanted to baby NIMHs about the only thing I'd do is the 1/10C or lower initial forming charge. If I really wanted the highest capacity *right away* then maybe I'd cycle them a few times (Before I use them for RC purposes).

Otherwise they're going to get this anyways from daily use.

 

[Radiophile]

Unless you are using them for some critical use where they need to have maximum capacity right away and for each use, I'd recommend just using the batteries, and when they need it, charge them.

You've got what's widely considered the best charger for NiMH batteries, and .5C - 1C is a good rate to charge them for best termination.

 

[Russel]

My C9000 method:

One break-in cycle when brand new.

Discharge to 1V and store in refrigerator if not in use.

Charge as needed, with a minimum discharge/charge cycle once every three months if no recharge is needed.

Break-in cycle once a year.

 

[TakeTheActive]

...I wanted to ask a question to the fellow flashaholics about their routine battery maintenance. I know the topics regarding chargers and batteries in various threads has been stripped, analyzed, recorded, disassembled, put back together, and eaten alive already <grin>. I've done my best to try and read them all but what I've failed to really find, and what I believe lots of people might be looking for, is how should I maintain my cells on a regular basis...

1. LEARN how rechargeable cells work.
2. DOCUMENT how YOU use your rechargeable cells (Lo/Hi current; Daily/Weekly/Monthly/or longer cycles).
3. MONITOR all 'Cell Health' indicators available to you.
4. CHARGE / DISCHARGE / CYCLE-REFRESH / BREAK-IN your cells, as needed, to maintain their optimum health.

...Once again, I know this is an open ended debatable question but I'll explain what I have, the routine I've put together, and then I'd appreciate any comments or deviations that other people may suggest.

Currently I'm using the C9000 charger with Duraloops all around (both AA and AAA's).

From what I've gathered in various threads and from the C9000 manual... this is what I have been following (assuming starting from a new pack of AA Duraloops):

Charge 1: Break-in (1-3 times).
Charge 2-9: Regular charges (at about 1000ma)
Charge 10: Refresh & Analyze
Charge 11-19: Regular charges (at about 1000ma)
Charge 20: Refresh & Analyze
Charge 21-29: Regular charges (at about 1000ma)
Charge 30: Break-in

<rinse and repeat from charge 2 again after charge 30 depending on battery performance>...

AFAICT, you've simply QUOTEd the Maha MH-C9000 Manual. :sigh:

What about:

1. DEPTH of Discharge?
2. DAYS BETWEEN Cycles?
3. AGE of cells?
4. DETERIORATION of cells (i.e. 'accidents')?
5. etc...

...

1. Is this a general good schedule to follow?
2. or should there be any deviations from this?
3. if so, what do you recommend?

1. IMHO, no.
2. Yes.
3. See first list above.

...I'll just add that I've developed a little Excel spreadsheet to accomodate the above schedule with inputs for Mah and voltage readings at certain intervals to keep track of the battery performance.

I had an Excel spreadsheet - BEFORE I started regularly reading 'CPF - Batteries Included'. Then I switched to PLAIN TEXT (probably a DATABASE would work even better, but, it's much too much effort for me right now), which I'll assume you've seen examples of (I'll post another at the end of this reply anyway ).

IMHO, monitoring *ALL* parameters is important:

• CHARGE Current (and charger)
• DISCHARGE Current (and device)
• CAPACITY @ 0.2C
• Internal Resistance
  - CLICK on my Sig Line LINK for methods to measure
  - Interpreting Maha MH-C9000 Impedance Check Voltage
• DAYS BETWEEN charges
• AGE of cell
• LSD vs non-LSD
• ...etc...

PLAIN TEXT Example:

Philips 1400mAh AA           [C] |   #9   #10   #11   #12
---------------------------------+---------------------------
09/20/09 BC900 Refresh3: 200/ 100| 1015  1158   n/a   n/a mAh
09/19/09 BC900 Refresh2: 200/ 100| 1006  1149  1152  1157 mAh
09/18/09 BC900 Refresh1: 200/ 100|  958  1043  1085  1069 mAh
09/18/09 RADSH Charge:  140/13Hr |   13    13    13    13 Hrs
09/15/09 BC900 Discharge:  100   |  ---   n/a   n/a   n/a mAh
09/15/09 C9000 Discharge:  100   |   76   n/a   n/a   n/a mAh
09/15/09 C9000 Discharge:  300   |  310   n/a   n/a   n/a mAh
09/15/09 BC900 Refresh:  200/ 100| 1116   n/a   n/a   n/a mAh
09/15/09 C9000 Impedance Check:  | 2.32  1.87  1.86  1.82 VDC
09/15/09 Sears Solar LED Lamp    |    x     x     x     x
09/14/09 BC900 Discharge:  100   |  ---   243   176   161 mAh
09/14/09 C9000 Discharge:  300   |  ---   989  1054  1024 mAh
09/13/09 BC900 Refresh:  500/ 250|  n/a  1213  1229  1173 mAh
09/12/09 C9000 Break-In: 1200    |  483   745  1064  1002 mAh
09/11/09 Sears Solar LED Lamp    |    x   n/a   n/a   n/a 
09/10/09 C9000 Impedance Check:  | 2.17  1.84  1.84  1.92 VDC
09/10/09 BC900 Discharge:  100   |  573   704   114   ~50 mAh
09/10/09 C9000 Discharge:  100   |    0     0    71     0 mAh
09/10/09 C9000 Discharge:  300   |    0    30   533   438 mAh
07/08/09 BC900 Test:  700/ 350   |  673  1201  1260  1202 mAh
07/07/09 BC900 Discharge:  350   | +792 +1141 +1483 +1358 mAh
07/06/09 BC900 Test:  700/ 350   |  737  1224  1270  1251 mAh
07/05/09 BC900 Discharge:  350   | +862 +1323 +1471 +1453 mAh
07/05/09 BC900 Test:  700/ 350   |  763  1182  1257  1254 mAh
07/04/09 BC900 Discharge:  350   | +981 +1423 +1454 +1436 mAh [TEMP: 47/50=113-111°F]
07/04/09 C9000 Discharge:  500   |  450   934  1025   971 mAh
07/04/09 C9000 Charge:     900   |  ---  +997 +1058   --- mAh
07/04/09 C9000 Discharge:  100   |   52   640   698   618 mAh
07/03/09 C9000 Impedance Check:  | 1.93  1.84  1.75  1.75 VDC
04/12/09 BC900 Refresh2: 200/ 100| 1190   n/a   n/a   n/a mAh
04/12/09 BC900 Refresh1: 200/ 100| 1172   n/a   n/a   n/a mAh
04/11/09 BC900 Refresh1: 700/ 350|  n/a   n/a   n/a  1247 mAh
04/11/09 BC900 Refresh3: 700/ 350| 1036   n/a   n/a   n/a mAh
04/10/09 BC900 Refresh2: 700/ 350|  982   n/a   n/a   n/a mAh
04/10/09 BC900 Refresh1: 700/ 350|  917  1189  1222  1253 mAh
04/10/09 C9000 Break-In: 1400    |  210  1062  1158   264 mAh#
04/08/09 C9000 Discharge:  100   |  108   695   779   781 mAh
02/18/09 C9000 Impedance Check:  | 1.95  1.90  1.75  1.86 VDC
01/23/09 BC900 Refresh:  700/ 350| 1120  1194  1262  1317 mAh
[Bought: mm/dd/02 -
 09/20/09:#2,3,4-NightHawk CO Alarm]

 

[TakeTheActive]

I added my replies / OPINION in BOLD GREEN within the (formatted) QUOTEs:

My C9000 method:

1. One break-in cycle when brand new.
   • MULTIPLE Break-In cycles until no further Capacity increase noted.
2. Discharge to 1V and store in refrigerator if not in use.
   • DISCHARGE to 0.9VDC
   • CHARGE to 25% of Capacity
3. Charge as needed, with a minimum discharge/charge cycle once every three months if no recharge is needed.
   
   • non-LSD: Monthly
   • LSD: Quarterly
4. Break-in cycle once a year.
   • [*]As needed, per Internal Resistance:
     • CLICK on my Sig Line LINK for measurement methods
     • Interpreting Maha MH-C9000 Impedance Check Voltage