pcnewman

I have,
(1) Hobbyzone 150mah 12c w/20 to 30 charges
(3) E-flite 120mah 14c w/20 to 30 charges
(3) Venom 150mah 25c w/ 4 or 5 charges
E-flite Celectra .1a to .7a variable rate charger.
I've been charging at .1a. This charger only has flashing lights to tell you when it's charging, almost finished charging and finished charging. I have to assume that it stops charging at 4.2v but I don't know.

Here's where I may have screwed up.
I had charged my batteries on a thursday and before I went flying Sat morning I topped them off. Each only took a few minutes and the Venoms less than the others. Is this the wrong thing to do?

I started out by running the 2 venoms in the T-28, each lasted about 9 min.s, then tried an E-flite and it only lasted about 1.5 min.s then another e-flite with the same results. So I put the Hz 150 in and got maybe 2 min.s

Later when I recharged the batteries the E-flites and Hz only took a few min.s to charge as though they weren't discharged hardly at all.
They Venom's charged as they had before, about 1 hr.

I haven't tried any of them since, so I'm not sure of their condition now.
What do you guys think?
Did I kill the older batteries by topping off and the Venom's could stand it because they are newer?
Maybe the T-28 motor was too hot and drawing to much?
Sorry for being so long winded!
Any help would be greatly appreciated.

guver

My Feedback: (325)

I'd say that your batts have a problem with internal or external connection or something else in the batts themselves , and it was not because you "topped them off"

Since you are rather charging "blind" and using them "blind" we only have little to go by (your data is very good though) , but a batt that charges quick and discharges quick is characteristic of a bad connection in the pack itself. The last little one I had happened to be internal tot eh cell itself.

pcnewman

Thanks, I tried one of the 120mah batts in a different plane that has a new motor this am. Same results. Must be the Batts. Set my Dx6i on 5min count down but can't hear the alarm. Too many years in construction and to little ear protection. Anyone know if there's a louder alarm that can be installed in the Dx6i?

RKS1949

I don't think there is? My DX7 is hard for me to hear too! I really have to listen close,to hear it! I just started to fly UM Planes and have a few 1S 150 mAh batterys. I'm not sure as to if I should charge the batterys before storage,or leave them at around 3.7-3.8 V? I charge all my battries before storing them,but have had a few 3S pack,to have a cell "swell" and die over the storage period. Should I charge them to 50% for storage? Thanks,Ron

Glacier Girl

My Feedback: (4)

pcnewman, do you have a watt meter? It's a must have for electric flight.

Would tell you pretty quickly what is going on with your packs. Will save you a lot of headaches and $$$.

From the sounds of it, and where a a watt meter would be able to tell you for sure, your HobbyZone and E-flite packs are on their way out. Voltage and capacity are what you need to be aware of, and not checking both can lead you down the wrong path.

The low flight time and quick recharge is a sign of a cell that's lost capacity. Voltage may check out perfect, but as soon as a load is put on it, it more then likely plummets.

Just hook up the meter between the pack and the plane, run the motor all the way up and watch the meter. Most likely when you check yours, you'll find the voltage drops like a rock pretty quickly on those packs, and not on the Venoms when you check them.

You can get a decent meter and the connector ends for dirt cheap from places like Hobby King.

A great meter. http://www.hobbyking.com/hobbyking/s...idProduct=6380

And the connectors you'll need. http://www.hobbyking.com/hobbyking/s...idProduct=9727

Saburo Sakai

Thank you pcnewman and GG! I have run into this same sitch-e-a-tion with the little 1s batts and, GG, I didn't know the point of attack with the meter.....until now! Thanks!
Without the benefit of the meter, what I do is, before flying, Iput a charged battery on the bird and run up the throttlefor a minute and ifshe stutters near full, ala the LVC, I know that battery istoast.
Happens with my E-flite PZ batts but hasn't happened with my Thunder Powers 160s yet.
Watt meter ison my "wish list" as of today. Merry Christmas!
And RKS, good question! GG or someone more experienced with LiPos will chime in........until then, be safe, and use the LiPo fire proof bags for storage. I sure do, after my little fire party!