I have an unused Fuze that I em keeping on a shelf until mine wears out. Should I keep it charged?
For long-term storage, it’s best to keep approx. 50% charge in the battery.
Charge it, put it on the shelf. It’ll slowly discharge as it sits there. Probably a good idea to charge it every year or two, since if you let it get too low the battery will be damaged.
The Fuze has a LiPo (lithium-polymer) battery.
I don’t know how much they differ from lithium-ion batteries, but
batteryuniversity says this about lithium-ion:
@ 40% @ 100%
charge. charge.
Capacity Capacity
Storage lost per lost per
Temperature year year
25C 4% 20%
40C 15% 35%
As previously noted: It will slowly discharge even when not in use, and you never want to let a LiPo get too low.
Great info, lee321987!
@lee321987 wrote:
<snip>
@ @ 40% @ 100%
charge. charge.
Capacity Capacity
Storage lost per lost per
Temperature year year
25C 4% 20%
<snip>
Ah, but since the 100% battery starts with so much more, it takes quite a while for the higher discharge _rate_ to leave the battery with less charge than the 40% one.
After 100% 40%
Year
1 80 38
2 64 37
3 51 35
4 41 34
5 33 33
6 26 31
etc
So, it takes _5 years_ for the higher discharge rate to lower the 100% battery to the same charge as the 40% battery. After that the 100% battery really goes to hell, but nobody is thinking about 5 year neglected storage, I hope.
But, the real story, I think, is not the self discharge rate, but the charge on the battery. Li-Ion are happier operating at less than full charge. IIRC, I’ve read that the lives of batteries that are only 1/2 charged (to 3.9v) are twice that of batteries fully charged (to 4.2v).
So, yes, you’re better off storing at 40%, assuming there is some way to tell that the charge is 40%. I also have a Fuze in reserve and this discussion prompts me to do this: I am going to use this reserve Fuze until the battery indicator show 2 bars. Then store it and periodically check the charge. When it gets to 1 bar, I’ll charge it, but only to 2 bars, and put it back on the shelf.
Bob
You do understand that I was talking about losing charge _capacity_, and not state of charge – right?
@lee321987 wrote:
You do understand that I was talking about losing charge _capacity_, and not state of charge – right?
Oh … no, I kinda missed that! Now, in regard to my previous post: never mind. Except the part about not fully charging it - I’m sticking to that part.
In that case, the _capacity_ falls like this:
After 100% 40%
Year
1 80 96
2 64 92
3 51 88
4 41 85