Can I trust these batteries??

[Tom Sanderson]

Hello guys! Long story short, I was unable to fly my I2 for a little over a year (due to heart surgery) and finally I'm back to normal. I'm anxious to get it back in the air of course, so today I charged everything up to see where I stand. I figured the two TB50's would be garbage, because they've been sitting unused for over a year. I don't remember if they were charged or uncharged when I packed them up last year. BUT, they charged with no errors and show 99% and 4.3v, and the other has 99% and 4.28v. That seems really suspicious considering how long they sat unused; right?

Do you guys think I can trust them based on the above info? What would you do? Thanks in advance!

Tom

 

[tibook]

What do they show under load?

I just went though 5 sets today, they are all at least 3.8 under load, seem ok.

I set them to discharge after 3 days. It’s not good to leave them fully charged if you’re not using them

 

[niki]

Hello guys! Long story short, I was unable to fly my I2 for a little over a year (due to heart surgery) and finally I'm back to normal. I'm anxious to get it back in the air of course, so today I charged everything up to see where I stand. I figured the two TB50's would be garbage, because they've been sitting unused for over a year. I don't remember if they were charged or uncharged when I packed them up last year. BUT, they charged with no errors and show 99% and 4.3v, and the other has 99% and 4.28v. That seems really suspicious considering how long they sat unused; right?

Do you guys think I can trust them based on the above info? What would you do? Thanks in advance!

Tom

They should be fine but you have to do a test with them just hoover at 1.5m until the batteries are depleted and land. Monitor the batteries performance while hoovering in DJI GO like @tibook suggest then make your conclusion how reliable they are. If one of the batteries start strugling by some reason then DJI GO will show battery error message after wich you should quickly land and probably toss that particular battery.

 

[Dobmatt]

They should be fine but you have to do a test with them just hoover at 1.5m until the batteries are depleted and land. Monitor the batteries performance while hoovering in DJI GO like @tibook suggest then make your conclusion how reliable they are. If one of the batteries start strugling by some reason then DJI GO will show battery error message after wich you should quickly land and probably toss that particular battery.

That would be a correct approach just to confirm the battery's willingness to co-operate at all. I will, however, perform yet another test pushing the throttle to the max while observing cell's voltage. Weak, deteriorated battery will eagerly exhibit voltage drop into red zone and temperature rise ...

 

[The Editor]

What he said ^^^^ ?

Just hovering will not put your packs under sufficient load to test their performance, you need some full throttle climb outs while monitoring individual cells to have confidence in the batteries.

 

[niki]

Applying full throttle should be done only after the hoovering test complete successfuly. Because if some of the batteries die while you are ascending that will not lead to safe outcome. If one of the batteries die while hoovering it is more likely the drone to have enough power for safe landing but if it dies in a stress test then probably the drone may shutdown itself before landing it.

What you guys just suggested is like in cold weather to power up the drone and apply full throttle to test the batteries. Some of the people reading the forum that don't have deep knowledge about lipos could do exactly that. Even good batteries will shutdown or will give a cell error in such situation. There are other factors as well that can contribute to the same outcome even if it's not cold outside.

The propper way is first to do a hoover and then to do a stress test. If the hoovering end with 10min flight time (much shorter than normal flight time) then it's obvious that the batteries have a problem. Doing a stress test on such batteries will definitelly end with a crash.

Soo..
One should do it on stages so to be safe. I personally will do first a hoovering test and if it is okey then on the next charge will do a stress test with full throttle. Also another safe approach is if one have sophisticated lipo charger with wich those tests can be made as well without flying at all.

 

[Dobmatt]

Soo..
One should do it on stages so to be safe. I personally will do first a hoovering test and if it is okey then on the next charge will do a stress test with full throttle.

This is exactly what we said, if you'll only pay enough attention:

"That would be a correct approach just to confirm the battery's willingness to co-operate at all. I will, however, perform yet another test pushing the throttle to the max while observing cell's voltage..."

 

[The Editor]

Applying full throttle should be done only after the hoovering test complete successfuly. Because if some of the batteries die while you are ascending that will not lead to safe outcome. If one of the batteries die while hoovering it is more likely the drone to have enough power for safe landing but if it dies in a stress test then probably the drone may shutdown itself before landing it.

What you guys just suggested is like in cold weather to power up the drone and apply full throttle to test the batteries. Some of the people reading the forum that don't have deep knowledge about lipos could do exactly that. Even good batteries will shutdown or will give a cell error in such situation. There are other factors as well that can contribute to the same outcome even if it's not cold outside.

The propper way is first to do a hoover and then to do a stress test. If the hoovering end with 10min flight time (much shorter than normal flight time) then it's obvious that the batteries have a problem. Doing a stress test on such batteries will definitelly end with a crash.

Soo..
One should do it on stages so to be safe. I personally will do first a hoovering test and if it is okey then on the next charge will do a stress test with full throttle. Also another safe approach is if one have sophisticated lipo charger with wich those tests can be made as well without flying at all.

If you had bothered to read my response I agreed with @Dobmatt who advocated hovering (not vacuum cleaning as you suggested) AND in addition doing full throttle climb outs.
That's why I said "What he said".

Your suggestion in post #3 made no mention of stress testing the pack(s) by pushing full throttle but simply 'hoovering' which will not properly evaluate their condition (but will probably get your floors nice and clean).
You have now added your additional post which agrees with Dobmatts & myself

 

[niki]

This is exactly what we said, if you'll only pay enough attention:

"That would be a correct approach just to confirm the battery's willingness to co-operate at all. I will, however, perform yet another test pushing the throttle to the max while observing cell's voltage..."

In your post It's not clear that this should be a separate test after the first one is successful.

 

[niki]

If you had bothered to read my response I agreed with @Dobmatt who advocated hovering (not vacuum cleaning as you suggested) AND in addition doing full throttle climb outs.
That's why I said "What he said".

Your suggestion in post #3 made no mention of stress testing the pack(s) by pushing full throttle but simply 'hoovering' which will not properly evaluate their condition (but will probably get your floors nice and clean).
You have now added your additional post which agrees with Dobmatts & myself

Hoovering = vacuum cleaning [emoji23]
I didn't knew that the people who are not racing their drones are actually vacuum cleaners or maybe dust blowers to be more precise.

 

[Dobmatt]

In your post It's not clear that this should be a separate test after the first one is successful.

You're right, it's not clear and it's irrelevant.

 

[Tom Sanderson]

Thanks for the advice guys. So they passed the hover test. I'm going to do one or two more hover tests just to be safe, then do the stress test. I'm just impressed that they work at all at this point!

 

[Dobmatt]

Thanks for the advice guys. So they passed the hover test. I'm going to do one or two more hover tests just to be safe, then do the stress test. I'm just impressed that they work at all at this point!

Good for you! BTW, no need to burn precious power for extra hover tests. If you've been observing dedicated battery status page in Go 4 app and didn't noticed any alarming voltage drop on any cell after several minutes of hovering, you're good to perform stress test.

 

[Tom Sanderson]

Oh wait - no guys, I’ve just been looking at the top of the main screen where it displays the battery percentage and then the overall voltage for each battery. I’m embarrassed to say I didn’t realize there was another screen I should be looking at?

 

[Dobmatt]

Oh wait - no guys, I’ve just been looking at the top of the main screen where it displays the battery percentage and then the overall voltage for each battery. I’m embarrassed to say I didn’t realize there was another screen I should be looking at?

Yes, this is a critical aspect of the entire story! Individual cell voltage, not the overall battery percentage on main screen, which is just a rudimentary way of battery state monitoring. Do another test, hover for 5-6 min until the battery(s) reach approx. 25-30C temp. If all cells are more or less evenly on green, start to abuse the craft slowly and observe voltage bars. Healthy ones may display voltage drop into yellow and red zone by the end of specified flight time ...