Who knows about LiPO batteries

[Donald]

So the battery in my RC helicopter is as dead as doornail because it says in a tree for 3 days with battery connected.

(Why is a doornail considered really dead?)

Connect to the basic charger and after 12 hours it shows 000%.

Apparently if the voltage is less than 3V the charger will not attempt to charge.

Are there any tricks? New battery is not cheap.

BTW - one needs to charge the battery in a LiPO battery bag in case it catches fire

 

[Kira]

..one needs to charge the battery in a LiPO battery bag OUTSIDE in case it catches fire.

 

[wings&wheels]

Is it a 'smart' battery? The battery pack in my drone cannot be resurrected if it goes completely flat as it doesn't retain enough energy to boot up it own brain....bad idea that was changed on later units.

There ahs to be a hack out there, try the RC forums, and do it outside. Good luck.

 

[Warstud]

Are there any tricks? New battery is not cheap.

Charge it enough from another battery to the point you can use the charger

 

[BrendanC]

hook the charger up to the dead battery but don’t start it. you need to add another power source in parallel to trick the charger into delivering power. normally this is a touch the contacts and let off thing as the charger should start pumping in power. just make sure if you do this you charge at a very low amperage to allow the battery it’s best chance at coming back.

 

[JohnnyG]

As to your other question. When doors were made from solid wood and nailed together, they would tend to loosen with use. In other words, the nails would work themselves loose by backing out.
This was fixed by bending over the points that stuck out from the BACK side of the door, thereby making them (door-nails) dead.

Not to be confused with "dead ringer", which is a whole other story.

 

[Cujet]

Charge it enough from another battery to the point you can use the charger

This!

 

[JHZR2]

So the battery in my RC helicopter is as dead as doornail because it says in a tree for 3 days with battery connected.

(Why is a doornail considered really dead?)

Connect to the basic charger and after 12 hours it shows 000%.

Apparently if the voltage is less than 3V the charger will not attempt to charge.

Are there any tricks? New battery is not cheap.

BTW - one needs to charge the battery in a LiPO battery bag in case it catches fire

There are no tricks if it went below 2v. Lesss than 2v and the copper current collector starts to dissolve. “Trick” it to charge again and that copper plates as dendrites. Those dendrites foster more playing of lithium or anything else, and pierce the current collector. Then you have an internal short and a major fire, even in a small battery.

 

[JHZR2]

Charge it enough from another battery to the point you can use the charger

This!

Not prudent if it went below 2v actual.

 

[Cujet]

Not prudent if it went below 2v actual.

I've done this for years, with acceptable results. This of course does not mean it's the safest answer. However if the battery is already junk because it won't charge, the risk of disaster is minimal if proper precautions are taken.

There is even a theory that such "zap" methods "burn" off the dendrites and restore adequate functionality.

 

[JHZR2]

I've done this for years, with acceptable results. This of course does not mean it's the safest answer. However if the battery is already junk because it won't charge, the risk of disaster is minimal if proper precautions are taken.

There is even a theory that such "zap" methods "burn" off the dendrites and restore adequate functionality.

The risk is minimal? We know we dissolve cu below 2v. There is no question about that. How much? Where will it plate? Maybe better questions that are harder to answer.

Disaster is relative. Even a small battery has a highly energetic release when it goes into thermal runaway.

 

[97prizm]

So the battery in my RC helicopter is as dead as doornail because it says in a tree for 3 days with battery connected.

(Why is a doornail considered really dead?)

Connect to the basic charger and after 12 hours it shows 000%.

Apparently if the voltage is less than 3V the charger will not attempt to charge.

Are there any tricks? New battery is not cheap.

BTW - one needs to charge the battery in a LiPO battery bag in case it catches fire

YouTube has some videos about "tricking " the batteries back to life. Ryobi, Mikita and others won't charge below a certain voltage. It's worth a shot.

 

[Carmudgeon]

YouTube has some videos about "tricking " the batteries back to life. Ryobi, Mikita and others won't charge below a certain voltage. It's worth a shot.

That's by design.

Lithium cells are capable of great performance, and have high energy density, but that also increases the risk when something goes wrong.

The tradeoff is that over-charging, and over-discharging them damages them, and in general, they like to live in a SoC sweet spot that sacrifices 40% of their capacity, if the aim is optimum durability.

By and large, BMSes insulate consumers from these constraints and try to reduce the risks, but can't eliminate them entirely, or prevent misuse. In practice, the vast majority of Lithium cells in use are treated like they're maintenance-free, but in principle, they are not, nor are they completely benign.

Everyone has their own level of risk tolerance, but they should at least be aware of the circumstances before making such decisions.