Query: Break-In on Camelions

[shobhitk]

Hi everyone,
i am quite satisfied with the performance of my MH C9000 charger. recently i bought 4 new NiMH Camelion 2700s (www .camelion.com) for my digital camera. i started with a Break-In which gave me ~2275 (+-50 mahs) for all the 4 batteries. this was my 1st break-in on the charger. so i was a little confused with the results....i have read that 2700 is an optimistic figure but isnt 2275 a bit too low for brand new NiMHs?...i was expecting somewhere between 2300-2500 mahs. are these batts good to go or not?
also now as i have the accurate readings after the break-in(2275 mah), should i use this value or the printed 2700 mah value for my subsequent break-ins on these batteries?

PS: all the batteries read 1.44 volts at the end of the break-in and after next 2 hours on the bay, all of them read 1.39 volts, after which i removed them from the charger.


Thanks

 

[shobhitk]

bump...

 

[shobhitk]

any suggestion would be helpful....

 

[Mr Happy]

Some batteries don't get up to full capacity until a few charge/discharge cycles. So you might want to use the batteries for a bit and then do another break-in cycle. If it were me, I would set the break-in capacity at about 2300 mAh rather than 2700, just to be on the conservative side.

 

[snakebite]

dont get your hopes up.
the ones i had were junk.worse yet they leaked!
about 2300 was their best cycle and downhill from there.

 

[shobhitk]

hi mr happy. got it. but it seems that 2200 mah on the first break-in is a sign that i shouldnt be too optimistic with these batteries...as i think is rightly proposed by my mate snakebite, especially after reading this thread- http://www.candlepowerforums.com/vb/showthread.php?t=239520

and yes 2300 mah seems to me a good deal for subsequent break-ins.

but mr happy if after more break-ins i get better results with increased mah then woudnt it lead a person to believe that the results shown by a break-in are not ABSOLUTE as is the usual conception....because if we get improvements after more and more break-ins then that means that the figure shown after a break-in is only indicative.
that brings one more ques to my mind. if we keep on getting slight improvements in mah after each break-in, then where does a person stop...how does one come to know if its done with break-ins? zero increase in capacity? impedance? etc..

 

[Mr Happy]

Of course the results from a break-in are absolute...the result you see is absolutely the capacity measured for that cell on that charger at that time for that break-in cycle

But seriously, what leads you to think it could be anything else?

The short answer to your question is that you stop with break-ins when the capacity is no longer increasing enough to matter, or if you run out of patience, or if you realize your batteries could be better employed in actual use rather than running break-in cycles on a charger :thumbsup:

 

[Turak]

The long answer...hehe

1. First run a Discharge cycle (if you want to compare the results make sure to use a discharge rate that equals .2C or as close as possible...for a 2700mAh cell that would be 540mA, so use 500mA)

2. Run a Break-in cycle (which is really; a 16-hour charge, a .2C discharge, and a final 16-hour charge). Note the rated capacity.

3. Run another Discharge cycle

4. Run another Break-In cycle. Note the rated capacity. Is it greater than the capacity from step 1. If YES, continue to next step, if NO go to 'End:'.

5. Run another discharge cycle....

6. Run a final Break-In cycle.

When all done, that would mean that the cell REALLY received 6 charge cycles and 6 discharge cycles.


End: If the cell doesn't reach at least 90% of its rated capacity...then in my opinion they are junk, especially if they are supposedly new, fresh stock.

My actual personal ratings for supposedly new cells are;

MH-C9000's Break-In capacity versus the rated capacity - Under 90%= Junk 90%-92%= Poor Cell, 93%-95%= Average Cell , 96%-98%= Good Cell, 99%+= Excellent Cell

So, for a new 2700mAh cell, they better get over about 2430, or they get taken back/returned.....but truthfully, I am pretty much sold on the LSD cells. Even though they are typically lower rated....in the long run, for my applications, they out perform all the regular higher capacity cells. I tend to let them sit for days at a time or have lower drain rate applications.

 

[shobhitk]

Mr Happy: Of course the results from a break-in are absolute...the result you see is absolutely the capacity measured for that cell on that charger at that time for that break-in cycle

that was exactly why i said that they r not absolute. they r abosulte for THAT Break-In Cycle. on a next break-in they might get increased mah. so yes they are absolute for that specific break-in...but for subsequent break-ins we might get increased mahs.
thanks for ur time, i appreciate it :twothumbs

Turak: thanks for the 'long answer' . very helpful, especially the battery ratings chart on mh-c9000's break-in.

so that leads to the conclusion that Camelion 2700s are not the best of the bread . ~2222 would mean around 82% ...too bad!