Battery Training

[Marine One]

Most rechargeable batteries have a manufacturers suggestion that you train them to get the most out of a charge. Generally it is suggested you take them all the way to zero charge several times so you will get optimum performance. (Not suggested while in the air.)

When this Newbie was flying the other night I got the first low battery warning with 2 bars on my ST16 drone indicator. I continued to fly close in when the second warning sounded and the drone became a little unstable. I was close to the ground and my position and landed safely with zero bars on the ST16 drone power indicator.

It seemed like there was a very short time between the first warning and second and if I had been out at a extended distance I would have not made it back.

Net/net will this end charge fade out get better as the battery breaks in?

 

[FlushVision]

Most rechargeable batteries have a manufacturers suggestion that you train them to get the most out of a charge. Generally it is suggested you take them all the way to zero charge several times so you will get optimum performance. (Not suggested while in the air.)

When this Newbie was flying the other night I got the first low battery warning with 2 bars on my ST16 drone indicator. I continued to fly close in when the second warning sounded and the drone became a little unstable. I was close to the ground and my position and landed safely with zero bars on the ST16 drone power indicator.

It seemed like there was a very short time between the first warning and second and if I had been out at a extended distance I would have not made it back.

Net/net will this end charge fade out get better as the battery breaks in?

You don't want to be still flying at the second warning. Simple.

If you are taking your H batteries down to zero you are going to bugger them up.

 

[Comtech]

You don't want to be still flying at the second warning. Simple.

If you are taking your H batteries down to zero you are going to bugger them up.

I would second that, and instead of discharging to 0, to discharge the batteries only to the OEM recommended level that would be based on chemistry of the battery and # of cells.

 

[Rayray]

Most rechargeable batteries have a manufacturers suggestion that you train them to get the most out of a charge. Generally it is suggested you take them all the way to zero charge several times so you will get optimum performance. (Not suggested while in the air.)

This is fairly correct with older recharge tech.
These LIPO batteries are a different breed of cat. They have no memory, no need to train.
You will ruin them instantly if you discharge below a certain voltage. BEWARE.
This LIPO info link is also found in the TH Help Sticky. A Guide to Understanding LiPo Batteries

At ease...

 

[FlushVision]

This is fairly correct with older recharge tech.
These LIPO batteries are a different breed of cat. They have no memory, no need to train.
You will ruin them instantly if you discharge below a certain voltage. BEWARE.
This LIPO info link is also found in the TH Help Sticky. A Guide to Understanding LiPo Batteries

At ease...

I know that DJI recommends the discharge of their Phantom 2 batteries to the point that they will no longer power up the aircraft once every 20 to 25 cycles and for that kind of battery it is good advice that will extend the battery's life span. This is definitely not the case with the H battery. If you run a H battery down to the point that the H will not turn on you will have a useless battery on your hands in no time.

 

[PatR]

Any maker that suggests lipo batteries be periodically discharged to a point they won't power up the aircraft is trying to sell more batteries. Only one caveat that would permit that, if the aircraft voltage minimum requirements are well above the minimum safe cell voltage.

Do not ever discharge a lipo below 3.2v/cell, and that's pushing it.

 

[FlushVision]

Any maker that suggests lipo batteries be periodically discharged to a point they won't power up the aircraft is trying to sell more batteries. Only one caveat that would permit that, if the aircraft voltage minimum requirements are well above the minimum safe cell voltage.

Do not ever discharge a lipo below 3.2v/cell, and that's pushing it.

The P2 will not power on if the battery is below a certain level so the battery is never below, or should not be below, the critical level to damage it. That is my understanding.

DJI recommended, for the P2 at least, that a 'rejuvenation' cycle should be performed every 20 cycles or so and that the way to do it is to leave the P2 switched on with props off (the P2 battery is not under load) until the aircraft powers down by itself...then recharge the battery. I have 3 P2 batteries still in service and the youngest of them is over two years old. They've all been through this process several times and are still performing well.

I would never do the same to a H battery...ever.

 

[Rayray]

Do not ever discharge a lipo below 3.2v/cell, and that's pushing it.

Definitely.
LIPOs are a great advance in battery tech. A TH battery is so powerful it can jump-start your car (please don't try this), but if misused they can be your worst nightmare, explode and burn with a fire so hot it cannot be easily put out.

 

[Marine One]

Thanx to all. I yield to your sage experience.

 

[Shadowolf]

This is based on the nicad and nickle hydroxide batteries. Lipos don't have memory. Lilo (lithium-ion) are best kept at full charge.

 

[NRRTRAINS]

to all , learn about LI PO batteries from the pro's , go to this site and read .A Guide to Understanding LiPo Batteries

 

[Windluv]

Best friends are battery scientists:
The lithium metal structure / matrix is much more fragile then nickel or lead as it is a soft metal. It will begin to collapse at faster rates then designed for when it is discharged below certain points (different li ion and li polymer systems have different points) say 80%. When you do an autopsy on a cell you will see the lithium decomposition as a greyish powder in the cell. This is also the element that triggers the occasional fires if the decomposition is enough to create a short in the cell. If a battery or a cell in the battery (remember 'a' battery is many cells) is discharged at a higher rate then the lithium structure can support it will also begin to decompose faster then designed for. All li ion based cells have this; it is how much structure is lost for each discharge/charge cycle that determines the battery life. This is typically determined by the recharge ratio which graphs for a certain discharge amount measured by mAmph or percentage of capacity, to the amount of charge mAmph that can be put back in. This ratio is always less then 100%; better batteries and how the battery is used determines this. Typically you will want to see recharge ratios in the 99.% range. If it was 100% this would allow perpetual motion machines to exist which we currently are not able to achieve.

In essence there is less lithium structure after each discharge to facilitate the ionic movement which is the potential energy stored. Higher rate discharges above design limits (lithium structure) will remove/damage more lithium structure faster, and draining energy beyond a certain fatigue point (typically 80%) of lithium will also damage the structure faster.

Discharging lithium structures to zero effectively collapses the structure.

Simple rule for lithium batteries: the less you discharge the higher your recharge ratio is, meaning the capacity for the next discharge cycle is as close to the last as possible.

One of the main issues with the current battery systems and telemetry provided is we do not get an amount of discharge mApmh actually used; we can only infer from a battery charger showing how much charge was put back in, and tracking for ourselves the differential. I was acclimated to battery R&D solutions with regards to precision required for development that were in the $100,000 range; that level of precision and performance is very different for $150 systems and even less for consumers.

 

[PatR]

Good info, and more reason for us to track # of cycles, flight time, voltage at end of flight under load, bounce back voltage after load is removed, charge rate, time to charge, mA in, and IR. Lots of work but those that are serious about this stuff really need to know what condition their batteries are in. For those doing commercial work it also helps establish reserve amounts for the cost of each flight. Part of the cost basis.