FlightPower 4900mah 6s1p charging problem

[oldsavage]

This is my first post and not how I wanted to start, but I have a problem.

I just purchased an AstroFlight #109 charger/discharger, FlightPower EVO20 4900mah 6s1p lipo battery and a FlightPower V balance module. Yesterday I charged and used the battery for the first time. The charger did everything the instructions said it would in all 3 modes and recognized 6 cells, charged at 2.5 amps, charging ended at 25.20 volts as it should. I strapped it in my new T-REX 600 CF and completed its maiden flight with no problems. Just a nice hover about 6" off the ground.

Today when i connect the battery to the ballancer, the ballancer recognized 6 cells and then the 6 lights flash meaning ballance is complete. The single red fuel level light is on, not flashing, meaning each cell has between 3.4 and 3.6 volts. When I start the charging process the AstroFlight #109 only recognizes 5 cells and 21.00 volts. I let it finish the 5s1, 3 minute phase 1 cycle and after 3 minutes the display went to 5s2, about 2 seconds it went to 5s3 and I stopped the charge.

This would be the batteries second charge.I was carefull to do everything correctly. Any help would be greatly appreciated. :dontknow

Thank you
Kevin

[WillJames]

I would bet that the pulsed mode on the astro cut your charge early and you over discharged the pack to 21 volts due to it never being fully charged. Pulsed charging of Li-Po's is NOT recommended and in our testing the V-Balance module is very prone to cutting the charge early during pulse mode no matter what the Astro reads voltage wise in stage 3 (pulsed stage) If you watch the display on the Astro, the pulse mode will take the pack voltage a good bit over 25.2, you can see it on your display.

I don't bash any product, but I can assure you that the Astro 109 has caused MANY people to toast FP battery packs and created more tech support calls to FlightPower USA than any other single issue and basically all issues combined. I hate to even say this, but it is the truth! I know with 100% certainty that our packs are not the only brand being destroyed by the 109's pulsed mode.

[oldsavage]

Thank you William for the info. I charged the battery at 1 amp twice on the first 3 minute stage of the charger and the voltage came up enough to get back to 6 cell. This charger looked very easy to use thats why I bought it. But if it charges improperly, I can see a new one in my near future. Any recommendations? A new charger is cheaper than a new battery. Also has this permanently damaged my battery?

Thanks again
Kevin

[Steve Rogers]

If you brought the pack back to life sucessfully there is a chance of a shorter life or possibly puffing it early on. I would definatly keep an eye on it. For a reasonably priced quality charger the Schulze ( http://www.espritmodel.com/index.asp?PageAction=VIEWPROD&ProdID=3067 ) is pretty decient for the price & works great with the Vbalancer.

[steve28]

does this pulse mode charging cause problems only when used in conjunction with the V-Balancer because the V-Balancer terminates the charge too early ?

Lets say you were to use a blinky balancer instead , a blinky doesnt have the ability to terminate the charge early and therefore the pulse charging continues until its finished and the balancer can be left connected after the battery has been removed from the charger to complete the cell balance before discharging . This would prevent an overdischarge situation from happenning would it not ?

[WillJames]

Our technical people say that pulse mode charging is not recommended for Li-Po's. No matter which balancer is used.