AT/KP chemistry problem.

[MrMel]

Hi,

I killed 4 x 6s1p 5000 AT Packs, they have 50% capacity left and wont hold more then 3.2 volt under 20amp, they have less then 20 cycles with 10C avg discharge rate on them.

Thing is, I have not a clue why.

I have treated them exactly like my other 8 x 6s1p 5000 FP & TP packs, the FP/TP is like brand new performance wise even though they have passed 40+ cycles.

- Storage at half charge, room temp.
- Fully charged only when rained in (a week or so)
- Never charged cold or hot.

(and I have other lipos with 275+ cycles on them, so my normal lipo handling is pretty safe I dare to say)

So, conclusion is that something that we "normally do" dont go well with the new chemistry of those packs.

Question is what.

It could be perhaps that they take severe damage by being fully charged just for a few days, or perhaps they dont like room temp.
Or I just got 4 bad packs, but I doubt it, since % degrading is equal between the two packs I used in series from start.

Anyone else seen simular behavior from those packs?

- Fredrik

[istandalone]

i hope your wrong about them being damaged by being fully charged for a few days. my kp packs usually go about 3-5 days between flights, and i always assumed that being fully charged for only that short period of time was fine. i'll have to cycle my KP's and see what comes of it, and i'll post back to you my findings. i hope your wrong though lol!

[joehelicopter]

Hi,

I killed 4 x 6s1p 5000 AT Packs, they have 50% capacity left and wont hold more then 3.2 volt under 20amp, they have less then 20 cycles with 10C avg discharge rate on them.

Thing is, I have not a clue why.

I have treated them exactly like my other 8 x 6s1p 5000 FP & TP packs, the FP/TP is like brand new performance wise even though they have passed 40+ cycles.

- Storage at half charge, room temp.
- Fully charged only when rained in (a week or so)
- Never charged cold or hot.

(and I have other lipos with 275+ cycles on them, so my normal lipo handling is pretty safe I dare to say)

So, conclusion is that something that we "normally do" dont go well with the new chemistry of those packs.

Question is what.

It could be perhaps that they take severe damage by being fully charged just for a few days, or perhaps they dont like room temp.
Or I just got 4 bad packs, but I doubt it, since % degrading is eecellsqual between the two packs I used in series from start.

Anyone else seen simular behavior from those packs?
er
- Fredrik

Call Mandy @Air Thunder ...I am sure they will back the product if you explain the problem.
I Think you should look at possible problems with your charger-4 batts with the same problem...look for the common link.....the charger:smokin:

[MrMel]

Already talking to mandy.

3 Different type of chargers, however, as stated, none of the regular chemistry packs are affected...

[MrMel]

I have a theory,


The Airthunder & Kongpower do have quite high self-discharge rate compared to normal lipos.

Could be that I used them, not charging right away and they self-discharged down to "dangerous" levels and stayed there longer then whats healthy, and therefor got damaged.

It makes sense since I tested cell by cell in one of my pack and 5 our of 6 was having severe capacity loss.

Well, at least its a theory, I gonna see if I can rig some tests and see if I can verify.