TB47 Batteries Down To 6 Minute Flight Time

[Charles R.]

I just got my Inspire 1 out for a flight its been a while since she has been in the air. MY 4 TB47's have been in storage for well over 3 months. They are not new batteries and have worked well for years I tried discharging them well below storage and recharging before the flight but the batteries are only good for about 6 minutes. Most have 40 to 60 charges but 6 minutes is disappointing to say the least. Is it possible to bring them back somehow? Any thoughts?

 

[myke]

I just got my Inspire 1 out for a flight its been a while since she has been in the air. MY 4 TB47's have been in storage for well over 3 months. They are not new batteries and have worked well for years I tried discharging them well below storage and recharging before the flight but the batteries are only good for about 6 minutes. Most have 40 to 60 charges but 6 minutes is disappointing to say the least. Is it possible to bring them back somehow? Any thoughts?

Hi Charles, I found one of my IS1 bettries went that way so based on previous experience with GPS gear I put it in the freezer for 2 days then discharged recharged a couple of times. Now getting around 15 to 20 mins with x5 on board.

 

[The Editor]

I just got my Inspire 1 out for a flight its been a while since she has been in the air. MY 4 TB47's have been in storage for well over 3 months. They are not new batteries and have worked well for years I tried discharging them well below storage and recharging before the flight but the batteries are only good for about 6 minutes. Most have 40 to 60 charges but 6 minutes is disappointing to say the least. Is it possible to bring them back somehow? Any thoughts?

DON'T whatever you do listen or take the 'advice' given above!
If you do you will have a ticking time bomb.
There is no way of knowing how much damage has occured to the cells internally by freezing them and they can catch fire at any point.
The reason is simple - a phenomenon called Dendrite Shorts.
Freezing lithium ion cells and then drawing high currents causes spikes to appear on the plates of the anodes. Normal charging causes the anodes to expand slightly but with tiny spikes now formed and an uneven surface and no way of knowing how large the spikes have grown a short can occur internally at any point with a resultant lipo fire.

If you are getting low run times from your packs then it is time to retire them - plenty of threads already on this.

Please, please DO NOT put your packs in the freezer - EVER. You could lose your house, or worse.

 

[myke]

Thank you for that warning. I was unaware of that particular phenomenon and having been in survey 35 years I am surprised that I have never had an issue . Can you offer advice on how the batteries that have been frozen can return to holding charge and then keep on working without incident?

 

[Starz]

Seems to be some differing thoughts on this subject and is an interesting read. A simple search for “freezing lithium battery” brings up many paragraphs of material. I’m not convinced that applying this process to something that flys through the air and can drop like a rock would be a good decision. It may be safe for other applications that can’t put a knot on your head when it fails. Since I dont have the technical equipment to diagnose the true condition of a battery and I’m not willing to roll the dice, I’ll just replace as needed.

 

[Stephen Bird]

Hi Charles, are you based in the UK? I have several TB47 & TB48 packs I rarely fly my I1 these days. Let me know if interested in purchasing any?

Dear Mr Editor, if this is not allowed then please remove the post, just trying to help a fellow pilot.

Regards - Steve

 

[Charles R.]

Hi Charles, are you based in the UK? I have several TB47 & TB48 packs I rarely fly my I1 these days. Let me know if interested in purchasing any?

Dear Mr Editor, if this is not allowed then please remove the post, just trying to help a fellow pilot.

Regards - Steve

Hello, Thanks I'm in the US

 

[Charles R.]

Back to my original Topic aside from freezing them which I would be very leary of that but thanks for the thought. What can I do to try and do to get more flight time will it involve deep discharging and recharging. What are the rest of you doing?

 

[gunner369]

Hello Folks, I store my batteries in the house during the summer months here in Mesquite, NV today its suppose to get up to 212F. Another question I would like to know, should I store my controllers in the house also, being its hot here, is it best for there batteries too, please advise anyone. Thanks in advance, Dave

 

[SanCap]

Back to my original Topic aside from freezing them which I would be very leary of that but thanks for the thought. What can I do to try and do to get more flight time will it involve deep discharging and recharging. What are the rest of you doing?

Nothing can be done, retire them.

 

[Charles R.]

That's what I was afraid of.

 

[Charles R.]

I just don't know if it is worth buying overpriced tb47';s to keep it going ?

 

[myke]

Seems to be some differing thoughts on this subject and is an interesting read. A simple search for “freezing lithium battery” brings up many paragraphs of material. I’m not convinced that applying this process to something that flys through the air and can drop like a rock would be a good decision. It may be safe for other applications that can’t put a knot on your head when it fails. Since I dont have the technical equipment to diagnose the true condition of a battery and I’m not willing to roll the dice, I’ll just replace as needed.

Couldn't agree more with your warnings and thanks. Where I come from in Canberra my Lithium batteries were kept in a garage lockup with no heating. Canberra would get to -5c through winter regularly so on reflection I'd say those batteries were getting very cold-frozen- many many times. Is the overall advice then : that you should always keep lithium batteries above zero degrees Celsius?