How long can you store fully charged batteries?

[scasanova]

Hi Everyone,

I've tried sifting through all the battery threads but none seem to address my question. Between work and a slow to arrive spring I'm struggling to find time to fly, partially because my batteries are at storage charge and I'd need to incorporate charging time into my flight window. How long do you typically keep batteries fully charged before running them down if you aren't able to fly? Thanks!

SC

 

[Phaedrus]

I will generally not let mine go more than a week before putting them on storage charge. Some will say less than that. Over many years of using lipos this has worked well for me.

 

[Eagle's Eye Video]

There are several pilots here who would set that timeframe at 2 to 3 days max... YMMV.

I will let others chime in, but I'd venture that not keeping your batteries fully charged for any extended time is even more important as the available battery stock ages. I've never seen any reports of a manufacture date more recent than 2017, so all these batteries are now going on 2≥ years old... including recently purchased units. The most recent manufacture date reported is October 2018 in the UK. I do not know what dates are being delivered to US distributors.

 

[Fred Garvin]

I keep my batteries at storage. If I’m going to fly that day, I’ll charge what I anticipate I’ll need. It’s no trouble dropping unused ones down to storage. I can fly out back practicing precision drills then put them back to storage mode. I usually have 1 to do as I typically charge 1 or 2 more than I need. If I have time onsite I’ll burn an extra battery but normally at a customer site I’m only doing what I’m there to do and then gone.

 

[PatR]

I get nervous after 3 days but have gone longer, with the longer usually to my detriment.

 

[Mrgs1]

There are several pilots here who would set that timeframe at 2 to 3 days max... YMMV.

I will let others chime in, but I'd venture that not keeping your batteries fully charged for any extended time is even more important as the available battery stock ages. I've never seen any reports of a manufacture date more recent than 2017, so all these batteries are now going on 2≥ years old... including recently purchased units.

We have October 2018 here, I've posted that here before. They are still being made.

Discounted Typhoon H batteries

Hey all. I discovered that Best Buy has put some Ty-H batteries on clearance online. They're 90 bucks plus tax - shipping's free. I also got lucky and found one at a local store for $74. Good chance to get a little money off if you're looking to up your battery count. They have the same...

yuneecpilots.com

 

[Mrgs1]

 

[FlushVision]

I leave all my batteries at storage level until the day before I expect to have a flight charging up the batteries I think I'll need the evening before the flight or, if I have time, maybe leaving one to charge up the morning of the flight. If it turns out that I've got a battery left over then I'll run that battery down to storage on site. So, for me, my batteries generally only remain fully charged no longer that around 16 hours. Note that any length of time that the batteries are at full charge will have some degree of negative effect on the batteries, so IMHO it is always best to charge up batteries as close as possible to the expected time of flight but also ensuring that they've cooled down before the flight leaving at least hour between the end of the charge cycle and shoving it into the aircraft. N.B. the controller battery can be charged up at any time and leaving it fully charged will not effect the battery.

To answer your question, then, I would say 24 hours but the shorter the better. All my TH batteries are at least 3 years old and still going strong. All my P2 batteries are at least 4 years old and I've only ever had one go bad on me.

As an aside, I know that Phantom 2 batteries are smart and will auto discharge to storage after 10 days. That, in my opinion, is far too long, but better than leaving the batteries fully charged for longer periods.

 

[Ren57]

As an aside, I know that Phantom 2 batteries are smart and will auto discharge to storage after 10 days. That, in my opinion, is far too long, but better than leaving the batteries fully charged for longer periods.

I hadn't flown my old Q500 for over a year and I'd left the batteries at storage charge. Went to check the batteries the other day (4 of them) an they're all shot! All got nice bulging going on. So all of them now need disposing of.

 

[Mrgs1]

I hadn't flown my old Q500 for over a year and I'd left the batteries at storage charge. Went to check the batteries the other day (4 of them) an they're all shot! All got nice bulging going on. So all of them now need disposing of.

The electrolyte decomposition occurs even faster if you overdischarge a battery or overheat a battery.

 

[FlushVision]

The electrolyte decomposition occurs even faster if you overdischarge a battery or overheat a battery.

Hence why I said it better not to fly a battery less than a hour after it's charge cycle has finished...give it chance to settle down and disperse any heat from the charge cycle if any.

 

[Mrgs1]

Hence why I said it better not to fly a battery less than a hour after it's charge cycle has finished...give it chance to settle down and disperse any heat from the charge cycle if any.

There's more heat when you pull it out of the copter after a flight than charging, that's probably where most damage gets done.

 

[PatR]

Most battery chemistries have a natural self discharge rate. Regardless of the voltage they are stored at they will lose voltage over time. That means you can’t expect to leave a battery sitting indefinitely with any hope of it being functional after sitting for long periods of time.

If we don’t periodically check our batteries and service the voltage level the one thing we can depend on is they will no longer be useful. A battery left at storage level for a year will more often than not have destroyed itself in that time period.

 

[Mrgs1]

Most battery chemistries have a natural self discharge rate. Regardless of the voltage they are stored at they will lose voltage over time. That means you can’t expect to leave a battery sitting indefinitely with any hope of it being functional after sitting for long periods of time.

If we don’t periodically check our batteries and service the voltage level the one thing we can depend on is they will no longer be useful. A battery left at storage level for a year will more often than not have destroyed itself in that time period.

That comment is common since really, would you leave your car I'm the garage without checking it? Any battery dependant electronics etc, batteries could of leaked, with something as volatile as these batteries, they deserve care and attention.

 

[PatR]

Common sense indeed, but sorry to say what should be common often isn’t anymore.

But now it’s published on the internet those lacking common sense have something to refer to...

 

[Ren57]

Most battery chemistries have a natural self discharge rate. Regardless of the voltage they are stored at they will lose voltage over time. That means you can’t expect to leave a battery sitting indefinitely with any hope of it being functional after sitting for long periods of time.

If we don’t periodically check our batteries and service the voltage level the one thing we can depend on is they will no longer be useful. A battery left at storage level for a year will more often than not have destroyed itself in that time period.

Indeed. I kept saying to myself "I must check those Q500 batteries, or give it fly". But life got in the way! By the time I finally got round checking them, it was too late. My stupid fault, I know.

 

[PatR]

If it makes you feel any better I can assure you that you’re not the only one that’s neglected them. Wait until you have a $2k pile of batteries sittin on a shelf while your called away for awhile...

As mentioned in another thread, life happens, with all the distractions associated with it. But if ruining a few batteries is the worst that ever happens we should feel fortunate.

 

[FlushVision]

There's more heat when you pull it out of the copter after a flight than charging, that's probably where most damage gets done.

Agreed. Unfortunately, though, that's one thing that we can't avoid. All we can do is do our best for our battery's health.