calcop

Hey everyone, I had recently purchased two ElectriFly LiPo (11.1V) batteries and had something very strange happen. After my first flight, I noticed that the top cell of the battery had bursted (inside) making it squishy. The battery (obviously) would no longer charge. My LiPo charger would give me numerous errors about the battery.

I continued flying with my other ElectriFly battery and had no problems until tonight. After about its 10th flight using the battery it did the same thing. The top cell had bursted inside and was squishy.

Thanks to Tower Hobbies, they are going to send me replacement batteries. My question is, has anyone else experienced this problem? What is causing this problem? I don't want to have to get replacements for these darn batteries every two weeks!

Anyway, let me know if you know anything about this problem. Or if you can recommend a better brand for light, small LiPo batteries.

-Matt

PilotLight

My Feedback: (1)

What size and what brand was the battery? Its makes a difference on the capacity of the battery and the "C" rating. That's the amount of "capacity-mulitiplier" the battery is able to supply reliably. For example a 1000Mah batter with a 10C rating should supply 10 amps with out a problem. If you need 15 amps, you need either a 1500 Mah 10C battery or a 1000Mah 15C battery.

My ThunderPower 1320 batteries are rated to 13C constant (17amps constant) and 20C burst (27 amps burst), but they still get warm during a hover. These are the Prolite series that include the balancing tap (plug).

Guess I should have read the Title of the post. What size of Electrify battery? 900Mah?????

calcop

It has a 15C rating and its 910 mA. It is the LiPo battery Heli-Max recommended.

Heli Bat

All I can say (and it might not be of much help) is that I bought my first GP recommened 910maH LIPO from my LHS just like you did. I bought an E-Flite Celectra Li-Po Charger #EFLC3005 for 1 to 3 cells. Got all this home and it all would not work. Took everything back to store and found out the the Battery was defective. Got new Battery and now it is fine. I have my Charger hooked up to a car battery so that it can get power. Then I hooked up the Li-Po. The settings are set to "3 cell" and "500ma". I was told not to go to the 1A (or 1000ma) setting as even though it seems to be very close. I adhered to the 500ma setting. It takes about 1 1/2 hours to 2 hours to charge. Getting about 15 min flight times. Thank you for the post as I will keep an eye on my LiPo. They say that the LiPo is a totally diff type of technology of battery.

Heli Bat

calcop

I will try charging it at a lower mA. I will see what happens when I get my replacements!

Thanks!

calcop

Do you really get 15 minutes of flight time charging at 500 mA? I need to try that. I only get about 3 minutes with the supplied 9 cell battery and get about 6-8 with my ElectriFlys (when they did not stop working).

I'm almost tempted to purchase the Kinetic heli because of these short flight times.

calcop

Okay, I got my first replacment battery. I hope this one doesnt bust too! I'm going to charge it at about 600 mA and give it a rest period before flying with it after charging. I'm hoping for that 15 minute flight! Havent seen it yet.

PilotLight

My Feedback: (1)

I have a Hobbico Quick Field Charger MK II and it will charge Li-po's up to 1 amp. "They" say you can charge a Li-po up to 1C. Meaning if you have a 910 Mah battery, you can charge up to 910 Mah so it should take 1 hour if its totally empty. My Thunderpower 1320's charge at 1 amp and take about 1 hour to charge and are never warm when finished. I'll bet you'll find you get better results charging at the lower amperage.

What setting were you using before? Were the batteries warm after charging? After flying? Did you go immediately from heli to charger to heli without cooling the battery? Do you have a balancer such as an Equinox from Great Planes or a Blinky? Ever check the balance of the pack?

Sorry for all the questions, but I think it would help someone trying to decide which battery to get when upgrading from stock 9 cell Ni-mh.

calcop

I was charging at about 900 mA before, I am charging at about 600 mA now. The batteries are never warm after charging. After use, yes they are warm. The battery has a built in circuit board that is supoosed to balance the pack.

Gunner461

Hey, I was reading your post and was wondering if your battery had (I didn't look it up on-line), two wires coming out of the (Charge port) or multiple wires. If you have a two charge port, then you will not be able to balance them. If there is a multi-port, then use an Equinox charger to balance all of the cells. It appears to me that ALLthe two wire batteries that are made by ElectriFly are being fazed out. It appears that as the POLIbatteries are growing in popularity, the technology is being improved also. Another tip is, you don't want to Jerry-Rig your connectors, try to run as straight as possible to the charger/battery. And try to minimize the length of wire you are running from your vehicle battery.
Good Luck!
Gunner461

P.S. Dumb question, how did you set the cut-off circuit in your batteries?Are you cutting the power at about 8.2? I'm wondering if you are draining them right to the max limits, and then the charger/batteries are having a hard time bringing the power back up to max?I have had this happen to an ElectiFly battery before.