Primary/Recharge - where to utilize?

[Justin13]

I have accumulated 7 lights over the past 10 days. Each light was purchased with an intended location and purpose. I have also purchased a bunch of rechargables and the 72 box of Surefire A123's.

For the lights that are left in the cars which will most likely only be used once or twice per year, is it wise to have rechargables sitting in them? Will I go to use them and have no juice after sitting all that time?

I planed on leaving a fully charged 18650 in those lights and a plastic bag with 4 primary A123's in it in the car as back up.

 

[Niconical]

If you have a light that can take a 18650 or 2x primaries, and you have both already, then the 18650 loaded and the primaries as spares is perfect.

Just remember to check the 18650 every few weeks or so.

One thing to bear in mind though is that this implies a light that will have some use. If it really is once or twice per year, then I'd suggest primaries only. This is not because the 18650 will self discharge too much, but because leaving a 18650 fully charged for extended periods has an effect on the long term capacity of the battery. I can't remember the exact figures, but whether storing in an unused light or a drawer, an 18650 that wont be used for months should ideally be stored partially charged, which kinda rules it out for backup light duty.

 

[Justin13]

I understand that, thank you.

I dont use two of the cars more than 2 or 3 times per year, they sit with trickle chargers on them. Might be wise to leave them with primaries.

My lights intended for home use will benefit from the rechargeables as we use them frequently. I bought 6 @ 18650 2400 mAh and 6@ RCR123 750mAh just for the hell of it.

I'm sure when I need them, they wont be fully charged and Ill be busting open the Surefires.

 

[was.lost.but.now.found]

One thing to bear in mind though is that this implies a light that will have some use. If it really is once or twice per year, then I'd suggest primaries only. This is not because the 18650 will self discharge too much, but because leaving a 18650 fully charged for extended periods has an effect on the long term capacity of the battery. I can't remember the exact figures, but whether storing in an unused light or a drawer, an 18650 that wont be used for months should ideally be stored partially charged, which kinda rules it out for backup light duty.

I believe I also read on Battery University that li-ion has a fixed maximum life, and even with the best care will only last a few years due to internal corrosion or something like that. It would stink to only get to use a $10 battery a half dozen times before it was done.

 

[Justin13]

I won't get into the "what's the best A123" posts before I do some reading!

I have quite a few surefire batteries, I hope I'm set when I need light.

 

[Niconical]

I won't get into the "what's the best A123" posts before I do some reading!

I have quite a few surefire batteries, I hope I'm set when I need light.

Well, I'll answer that one for you now anyway.

Option 1 you already have, a nice big box of Surefire brand.

Option 2, for when that starts running low, or you want to stock up, batterystation do a CPF special, a box of 50 for $60.
You won't get a better price/quality ratio than that for CR123A.

 

[anonymoususer]

Justin, i had the same question and according to SilverFox's tests, it is perfectly reasonable to have a fully charged Li-Ion sit for years at a time ready for use. Here is a thread with a link to another thread with lots of information: http://www.candlepowerforums.com/vb/showthread.php?t=264543