I switched from NiCad’s to Hyperion G3 LiFePO packs for all my receivers. No more NiCad’s as getting Sanyo brand in the higher capacity were harder to come by. Even the individual cells usually had to be ordered.

I bought the Hyperion brand because they were the only ones who had their own complete system with chargers, all kinds of packs, battery checker (more on this later) and all of the possible adapters you might want for charging, balancing and connection to circuit. At 6.6 volts no regulator required.

I am no electrical or electronic expert. The tests I performed were what I considered common sense and what I was capable of with the equipment I had on hand.

Some of you will claim there is no difference in what charger you use and I don’t have the electronic equipment to confirm or dispute this. I will tell you that after I had seasoned several of these batteries using a variety of chargers I set up a simple test bench to compare the charges I owned against the Hyperion brand.
I used:
Thunder Power TP-1010C with TP210V balancer
Thunder Power TP 610C
Hobby King Turnigy Accucel 6
Hyperion 6060i

The packs tested were 1700 mAh, 2100 and 3000 two of each. In all cases all of the chargers worked as expected. Consistently the Hyperion charger topped the battery off at 98 to 99%. The others were anywhere from 96% to 98%.

I used the Hyperion EOS Sentry battery checker http://media.hyperion.hk/dn/sentry/ to check the batteries. I know it has been said there is no way to use voltage to check these cells however since I had the test bench set up to draw the batteries down I tried a simple test of drawing the batteries down under different loads through my Astro Flight load meter. The load meter recorded the draw the EOS Sentry plugged into the balance jack recorded the voltage allowing me to scroll through and observe the remaining usable energy in percentage. When the batteries reached a predetermined level the draw was removed and the pack was allowed to bounce back and stabilize. Then the batteries were charged and the amount put into the battery was compared to the readings of the resting battery after it had stabilized. Every time no mater the capacity of the battery or the draw placed on the battery the EOS Sentry accurately within a few percentage points matched the charge returned to the packs. Being of the belief that bench testing is good but testing in actual service is better I continued this for several months off and on as time allowed and even as the packs became over a year in service the EOS checker has always been within a few percentage points.

I have used these packs now for over 2 years randomly checking the packs and I am convinced the EOS Sentry does its job as expected. I have actively flown a few non critical models as low as 20% usable left without problems. This confirms what everyone says about a flat discharge rate but with this checker and a little attention the usable time left on the pack in my opinion becomes as predictable as any other packs including the NiCad’s I loved so much. I fly with confidence and the EOS Sentry stays in my pocket at the field and I check my planes every time. An added bonus is checking the lipo pack before installing it in my plane for a flight. Twice now I have mistakenly picked up a mostly depleted pack to put in my model but caught it first when I did a quick check with the Sentry. Others I know have not and it has cost at least one his favorite plane.

Before buying a checker for the lithium cells read the online reviews and make up your own mind.