Tag Archives: lithium polymer

R/C micro Li-Po batter charger testing

It’s come to my attention, that the little battery chargers that came with the various helicopters, might not be working up to par. Taking longer than I want to charge is one thing, but not charging properly is another entirely! A recent visit to the hobby shops indicated that it’s common for them to fail. But, they should be easy enough to test to see if they are applying a full charge by the simple use of a multi-meter.

Thus, I dug up my trusty Fluke (it must be over 25 years old now), put in a new 9v battery and started some testing.

All batteries here are Lithium-Polymer (Li-Po) 2-cell 7.4v batteries. 2 of the batteries tested are for the Blade CX3, the other for the Madhawk 300. Here is a link to the chart I created to document the batteries I’ve used.

  E-Flite Battery Charger ExceedRD Battery Charger
Exceed-RC 7.4v 1000mAh 8.4v     8.4v    
Tenergy 7.4v 900mAh 8.43v     8.43v 8.43v  
E-Flite 7.4v 800mAh 8.43v 8.38v   8.43v 8.43v  
Hyperian VGX3 #1 8.43v          
Hyperian VGX3 #2       8.43v 8.43v 8.44v

Results

Testing so far indicates that the chargers, although slow, are doing the job. One battery, the E-Flite 800mAh seemed a little down on power during the 2nd cycle of the test. It might already be suffering some degradation of performance. If that’s the case, it’s pretty pathetic. I plan to run each through at least 3 charge cycles to get a decent dataset.