Charging New Lipo's

[DaveScott]

In a posting on this forum, I read the following:
‘Lipos are shipped with an inhibitor for safe transport. So always break in new lipos.. charge to full and then discharge to storage level (3.8V/cell) five times.’
Does this literally mean that I sit down, fully charge the battery, then discharge it, fully charge it, then discharge it five times? Thank you.

[DominicD]

Discharge = fly them.

[DaveScott]

Originally Posted by DominicD

Discharge = fly them.

Thank you - Much more fun rather than waiting for a charger to do the job.

[DominicD]

Just set your timer to half of what you expect it to be.

[DominicD]

I will usually do 2-3 half flights, and then Ill just fly from there, I dont think we need to baby new packs like we use to have to.

[learnedthehardway]

I try to cycle them twice with my charger then take it easy the first few flights but haven't noticed any difference when doing it as opposed to just flying them normally right away

Modern lipos are a far cry from the 1c max charge lipos. Chargers are better these days as well.

Don't leave them fully charged for more than a week or so at a time and don't fly them to lvc all the time and they'll be fine.

[DominicD]

Originally Posted by learnedthehardway

Don't leave them fully charged for more than a week or so at a time and don't fly them to lvc all the time and they'll be fine.

There is one point that I disagree with heavily, I never leave my packs charged for more than a few hours.

[learnedthehardway]

Originally Posted by DominicD

There is one point that I disagree with heavily, I never leave my packs charged for more than a few hours.

Definitely something I've actually seen evidence of being detrimental but it has always taken close to a month of sitting charged to have a noticeable effect.

Had a Align Hi Power 3s 2100 sit charged for over a year without any noticeable effect. Had some Gens Ace 6s 1200's sit charged for 5 weeks and they were never the same. Nothing major, the cells just settle in between 4.10-4.15v after charging instead of the 4.18v they would settle at before. Still working fine 7 months later and counting.

Abused the snot out of every rc truck and heli lipo I've ever owned and never had any issues leaving them charged for 7 days or less. If I had expensive 700 class lipos I'd probably not go past 3 days but have no problem leaving 6s 1200-1350mah 450 or 3s up to 4000mah packs charged for a week.

Hasn't bit me yet anyway and noticed cheap lipos tolerate it better than expensive ones for some reason

[DominicD]

I've gone through HUNDREDs of lipos since I started the hobby ten years ago. I have no real evidence to back up my claims, I just noticed packs kept their punch if I didnt charge the night before flying.

[betty]

Your theory is really funny by saying cheap lipos tolerate it better than expensive ones for some reason. So your Align and Gens Ace lipos are cheap or expensive ones?

Originally Posted by learnedthehardway

Definitely something I've actually seen evidence of being detrimental but it has always taken close to a month of sitting charged to have a noticeable effect.

Had a Align Hi Power 3s 2100 sit charged for over a year without any noticeable effect. Had some Gens Ace 6s 1200's sit charged for 5 weeks and they were never the same. Nothing major, the cells just settle in between 4.10-4.15v after charging instead of the 4.18v they would settle at before. Still working fine 7 months later and counting.

Abused the snot out of every rc truck and heli lipo I've ever owned and never had any issues leaving them charged for 7 days or less. If I had expensive 700 class lipos I'd probably not go past 3 days but have no problem leaving 6s 1200-1350mah 450 or 3s up to 4000mah packs charged for a week.

Hasn't bit me yet anyway and noticed cheap lipos tolerate it better than expensive ones for some reason

[jhamel]

I asked Dave (Progressive RC) about how to "break-in" new LiPos a few years ago. He told me to fly the helicopter as hard as I like for the first 5 flights or so, but to only fly them up to 50% capacity discharge for those first 5 flights.

[Slyster]

I find IR's are truly higher than after 5 flights or so... so I just set my charger to auto cycle the packs. Then again.. I only fly one pack per heli (2 packs total.. fast field charge) and only replace them every 2 or 3 years so it's nothin'

[betty]

First 5 flights as hard as you like. After it, 50% capacity discharge? Do you mean this?

Originally Posted by curmudgeon

He told me to fly the helicopter as hard as I like for the first 5 flights or so, but to only fly them up to 50% capacity discharge for those first 5 flights.

[jhamel]

No. After those first 5 flights, you should safely discharge them down to 20% capacity. This opens up a new subject; what is 20% capacity? The capacity stated on the label may not necessarily be the true capacity. Also, capacity degrades over time even if you baby the batteries. It is my understanding that
3.74-3.76v per cell is generally considered a good surrogate of 20% capacity.

For instance, my 4400mah packs are about 1 year old and have about 75 flights each. According to what's on the label, I should be able to consume 3,520mah to get them down to 20% capacity. In reality, they reach 3.76v/cell (80% capacity consumed; 20% capacity left) after only 3000mah consumption.

[betty]

OK. 20% Capacity. But the theory of the first five seems to be dangerous if we fly as hard as we can.

[Xrayted]

Originally Posted by betty

OK. 20% Capacity. But the theory of the first five seems to be dangerous if we fly as hard as we can.

All he is saying is not to fly the pack down to the usual 20% remaining for the first five flights or so.....maybe only 50% instead of the typical 80% used, so the first five flights will be shorter

This is to be nicer to the packs until they are "broken in" a bit before depleting them down as far as you normally would which in itself is debatable as there is no real evidence that there is even such a thing as "breaking in" a lipo, or that failing to do so has any bearing on the life of the battery. Like many things, most are just anecdotal stories or methods passed from one modeler to another. Nothing dangerous at all about flying hard with new packs, but do whatever makes you feel the most comfortable.

[jhamel]

I have not been able to find objective evidence to support the practice of battery break-in, at least not from a legitimate source with graphs and references. I figure if Dave says to just discharge the packs down to no lower than 50% capacity for the first 5 flights or so, and aggressive vs. mild flight style for those first 5 break-in flights does not make a difference, that's probably as solid as the information is going to get, at least for now. I guess I could have probed a little further and asked him what 50% discharge means; half of the capacity written on the battery label vs. 3.85v/cell?

As far as how fast to charge the packs, Lucian Miller discussed this on the "All Things That Fly" RC podcast about 4 years ago. He mentioned that LiPo health is better maintained when packs are charged at no higher than 1C rate. He mentioned that routinely charging at faster than 1C rate reduces the potential useful life of the pack. Sadly, he did not provide supporting evidence. He also did not define "useful life". He also did not present real numbers. How many "useful" cycles can one expect when one charges at 1C vs. charging at 3C? That would have been helpful.

For me charging at 1C rate at the field does not work as I would be waiting for packs to charge before I can fly next. 2C is about the fastest I've needed to charge to stay ahead with charged packs. If I am sharing the field with other guys, then I charge at a slower 1.5C rate.

[DominicD]

IMHO

Owning multiple packs per heli that you take care of is MUCH worse than owning 1 lipo per heli that you use and abuse and replace more often.

[Xrayted]

Originally Posted by curmudgeon

I have not been able to find objective evidence to support the practice of battery break-in, at least not from a legitimate source with graphs and references. I figure if Dave says to just discharge the packs down to no lower than 50% capacity for the first 5 flights or so, and aggressive vs. mild flight style for those first 5 break-in flights does not make a difference, that's probably as solid as the information is going to get, at least for now. I guess I could have probed a little further and asked him what 50% discharge means; half of the capacity written on the battery label vs. 3.85v/cell?

As far as how fast to charge the packs, Lucian Miller discussed this on the "All Things That Fly" RC podcast about 4 years ago. He mentioned that LiPo health is better maintained when packs are charged at no higher than 1C rate. He mentioned that routinely charging at faster than 1C rate reduces the potential useful life of the pack. Sadly, he did not provide supporting evidence. He also did not define "useful life". He also did not present real numbers. How many "useful" cycles can one expect when one charges at 1C vs. charging at 3C? That would have been helpful.

For me charging at 1C rate at the field does not work as I would be waiting for packs to charge before I can fly next. 2C is about the fastest I've needed to charge to stay ahead with charged packs. If I am sharing the field with other guys, then I charge at a slower 1.5C rate.

I agree. All we have is advice from some in the industry, but still no real data that proves any of it. Doing such test would require a lot of variables to be closely controlled and very time consuming.

It certainly cant hurt to take some of these measures, so I think that is what most work with within reason. I did the 5-6 charger cycles on my new packs for years, but then decided to just roll with it about 1.5 years ago and slapped in two new Pulse 6S packs I had purchased during a Christmas sale and started doing 200A pull speed runs on the very first flights.

Those packs are still going strong today with good IR no differently than any of my previous packs that were babied were. Im now using a max of 3-4 packs and fast field charging, so much less hassle than keeping up with multiple batteries

[betty]

OK, now I understand his meaning. We all here to discuss how to use lipos more scientifically. But yes, personal experience is also very important.

Originally Posted by Xrayted

All he is saying is not to fly the pack down to the usual 20% remaining for the first five flights or so.....maybe only 50% instead of the typical 80% used, so the first five flights will be shorter

This is to be nicer to the packs until they are "broken in" a bit before depleting them down as far as you normally would which in itself is debatable as there is no real evidence that there is even such a thing as "breaking in" a lipo, or that failing to do so has any bearing on the life of the battery. Like many things, most are just anecdotal stories or methods passed from one modeler to another. Nothing dangerous at all about flying hard with new packs, but do whatever makes you feel the most comfortable.