[Elecraft] KX3 and charging batteries (when, and why do they get hot?)

[Arno Dienhart]

Mark,
 
Having thought about this some more, I believe your point below is hitting
the nail. My BAT MIN was still at the factory default of 10V, which
obviously meant still lots of capacity. So the batteries were still quite
full and thus got warm soon and repeatedly.
 
Phew! I am not worried anymore. Thank you again!
 
73,
Arno kg7bjm
 
 
 
 
>> >>When should such batteries get charged, at what voltage level?
 

>>Don't let them go below 1v per cell...about 8 volts total on the KX3 

display...8.5V would be safer.  Elecraft recommends setting the BAT MIN menu
to 

8.5 V (KX3 Owner's Manual Pg. 36) to give you some warning that you need to 

think about recharging.  This is about 1.06V per cell.  The KX3 will shut
down 

at 8 V which is about 1V per cell, very near the absolute minimum for NiMH 

chemistry.  There isn't much energy left below 1.06v per cell, so running
them 

below that level really doesn't give you much extra operating time.  Some
folks 

set the BAT MIN to 9V to give them more warning and plenty of time to finish


their QSO and shut the station down.