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-   -   Storage charge Lipos (http://www.Wattflyer.com/forums/showthread.php?t=74355)

Ziet 08-24-2014 01:12 PM

Storage charge Lipos
 
I'm sure the answer to this question is in another thread but I cant find it so here goes. When I put my LIPOs in storage charge, can I top them UP when I wish to fly or should I use them from the storage charge!

Thanks ????

JetPlaneFlyer 08-24-2014 01:59 PM

You top them up to fully charged before flying. Just put them on a normal charge program.

Flysohigh 02-08-2015 02:27 AM

Storage mode for more than a week of non use besides that top them up and fly fly fly

fhhuber 02-08-2015 03:06 AM

Storage charge is actually almost on LVC for some setups...

Flysohigh 02-08-2015 03:24 AM

I always storage chg my packs after flying no matter what, always worked for me and never had any issue with any of my packs....

JetPlaneFlyer 02-08-2015 08:38 AM

Providing I havent accidentally over-discharged a battery I just store them at the voltage they come off the plane, typically 3.7-3.8v

From my understanding as long as the batteries are not fully charged and no fully discharged they are ok to store, the precise voltage is not really important.

fhhuber 02-08-2015 02:02 PM

Quote:

Originally Posted by JetPlaneFlyer (Post 968290)
Providing I havent accidentally over-discharged a battery I just store them at the voltage they come off the plane, typically 3.7-3.8v

From my understanding as long as the batteries are not fully charged and no fully discharged they are ok to store, the precise voltage is not really important.


Yes and no..

Best for LiPo battery life expectancy is 3.7v/cell and 38F for storage.
Don't go below 32 F (0 C) or above 90F for extended storage.

The further you are from there the faster the packs will age.

Someone did a lot of testing to figure that out. I can't remember exactly where I saw all of his graphs of relationship of voltage vs temp vs pack life.

Best pack life I have had so far I was storing the packs in my fridge at LVC (3.6 to 3.8 V/cell) during the week, charging the night before going to fly.

JetPlaneFlyer 02-08-2015 02:12 PM

Strange then that all chargers aim for 3.8-3.85V when you use the storage function. I also use the fridge for long term storage, but for packs i use regularly i tend to just leave them at room temperature.

fhhuber 02-08-2015 03:30 PM

not much difference from 3.7 v/cell to 3.9 v/cell. The longevity curve is nearly flat in there

JFonseca 04-06-2015 05:22 PM

If you come from the field with 1 full battery, and you know you probably will fly next weekend, what will you do? Leave it as it is, or bring it to storage voltage?

Thanks,
JFonseca

Brian VT 04-06-2015 05:36 PM

Quote:

Originally Posted by fhhuber (Post 968304)
not much difference from 3.7 v/cell to 3.9 v/cell. The longevity curve is nearly flat in there

Good to know. My Hyperion EOS 0606i wants me to store at 3.9v/cell.

Quote:

Originally Posted by JFonseca (Post 971909)
If you come from the field with 1 full battery, and you know you probably will fly next weekend, what will you do? Leave it as it is, or bring it to storage voltage?

Thanks,
JFonseca

I would drop it to storage voltage if I had the time. If not, I wouldn't loose much sleep over it unless it was an expensive ($20+) battery.

JFonseca 04-06-2015 05:51 PM

My batteries are 6s 5000mAh and are rated between 40 and 60C, so their price makes me want to keep them at their best health ;-)

I used to charge the batteries when I arrive home, so they would be ready whenever I want. Between work and family, in the last 4 years, it could pass 3 4 months between fly days, so I kept them at full for long periods.

3 of 4 batteries died this year when I returned to be more regular, with 2 or 3 days per month.

Now I fly almost every weekend. I charge the batteries the night before, and in the night after flying I bring them to storage voltage.

Every charge-discharge cycle brings the battery closer to the end, but my doubt was what could be more harmful: one more discharge-charge cycle or keeping the battery at full for 1 week?

JetPlaneFlyer 04-06-2015 06:14 PM

Leaving the battery fully charged is definitely to be avoided. For best battery life you should minimise the time spent fully charged as far as reasonably possible. Best to charge just before flying and if for any reason you don't use a battery discharge it as soon as possible.

In the real world of course this isn't always possible. Leaving them charged a while as a one off wont do appreciable damage keep repeating it and it all adds up.

I've invested in a powerful charger so i can charge just before flying, i can have them all charged in 45 minutes or so.

Flysohigh 04-06-2015 06:14 PM

I never charge and leave charged more than 1 hour, i charge the morning when going. The IR will deplete the same as over discharging them below 3.0v

fhhuber 04-06-2015 06:54 PM

You can get more than 300+ high demand (100+ amp from a 20C/40C burst 5000 mah pack) cycles out of a pack. THEN move it to lower demand for another 300+ cycles.

Generally my LiPo packs die from old age before they die from cycles. Regardless of cycle history I note decrease in current delivery capability (lower effective C rating) at 2.5 to 3 years. Then over the next year the capacity and current delivery keep declining.
That is with good storage practices.

Poor storage can kill a pack quickly. Store full charge in a hot car and its potentially destroyed in less than an hour.


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