Eneloop 2500 mah batteries

[lane zeitler]

Just received my Sanyo eneloop 2500 mAH rechargeable batteries niMH cells......will start the charge cycle when I get home from work tonight. How long should I charge them for...this will be the first charge and I have not used the radio yet at all with these new batteries. 

Also, if I keep the xmit power down to about 3watts what kind of operation time can I expect with casual SSB xmissions? Any thoughts on this are appreciated, thanks.

LCDR Lane Zeitler
Ku7i
JH1JCM
Forward Deployed 
US Naval Hospital 
Yokosuka Japan
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[KE6BB]

Lane,Walter hit the nail on the head.  The KXBC3 will not overcharge your cells, and its thermal sensors will shut down the charge cycle if the cells reach their temperature limit, 0 to 40 deg. C as Walter mentioned.  Charging will resume once they cool down.  New cells shouldn't need much charging, but a 4 or 8 hour top-off won't hurt them.  A 16 hr. charge won't hurt them either, but you will waste a lot of energy in heat since any energy that cannot be absorbed for charging because the cells are fully charged is converted to heat.  It can get a little scary because the KX3 gets pretty warm as the cells reach full charge, but the KXBC3 is a solid conservative constant current design for 2000 mah or larger NiMH cells.  You will eventually learn to trust it.      MarkKE6BB
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[Greg Troxel-2]

  Just received my Sanyo eneloop 2500 mAH rechargeable batteries niMH
  cells......will start the charge cycle when I get home from work
  tonight. How long should I charge them for...this will be the first
  charge and I have not used the radio yet at all with these new
  batteries.

The most important thing to avoid is running down one cell to 0 while in
use because of differential charge/capacity.  But as long as BATMIN is
>= 8.4, that's not too likely (1.05 Vpc under load, or one at 0 and 7 at
1.2Vpc).

I just got 16 Sanyo Eneloop 2000 mAh cells.  I first discharged them
individually to 0.9V at 200 mA with a Maha C9000, and obtained 1398 to
1414 mAh.  I then did refresh-analyze with 1000 mA charge, 200 mA
discharge, and got 1783 to 1855 mAh.  They are rated at 1900 mAh
minimum, but I hadn't cycled them multiple times yet, and I'm
discharging at 200 mA rather than the specified 100 mA rate.  The 1783
mAh cell did 1917 mAh on a second cycle.

So I conclude that the eneloop 2000 cells I got are good quality and
honestly marked about capacity, and when delivered were at about 77%
state of charge.

So while the recommendation of others to charge for 8h is sound, I'd
recommend that you get a Maha C9000 and test your cells :-) That's not
so important with new sanyo cells (because every battery I've ever seen
from Sanyo has been ok when new), but I've found that cells wear out
over the years.

Way more detail than is useful, semi-organized:
  http://www.lexort.com/blog/12v.html
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