Reminder: rechargeables

Posted by: teacher

Reminder: rechargeables - 01/10/20 08:54 PM

A reminder that rechargeable batteries and devices do best when periodically recharged. How often depends on the device; some every three months, others yearly.
Posted by: KenK

Re: Reminder: rechargeables - 01/12/20 02:25 AM

I've found that my Eneloop NiMH batteries need to be recharged every 4 months if not used. I thought they'd have a better shelf life.

Btw, I've completely stopped using standard alkaline AA's and AAA's due to leakage. Now only using NiMH and lithium batteries.

My Bosch hand tool NiMH batteries seem to have much better shelf life, but I still try to check them every 6 months or so.
Posted by: haertig

Re: Reminder: rechargeables - 01/13/20 06:02 AM

I just did some recharging today after seeing this thread. It had been several months (6+ probably). I was surprised to find that my LiION's had held their charge slightly better than my Eneloop NiMH's. I would have expected just the opposite.

I thought Eneloop's claim to fame was a longer shelf life (at the expense of total capacity) when compared to non-Eneloop NiMH's. I don't have any non-Eneloop NiMH's to compare to, but the LiION (AW brand protected 14500's specifically) held charge better than the Eneloops.
Posted by: Eugene

Re: Reminder: rechargeables - 01/13/20 02:16 PM

Remember batteries don't discharge in a linear curve (NiMH, Alkaline, etc)

https://www.google.com/search?client=firefox-b-1-e&biw=1232&bih=674&tbm=isch&sxsrf=ACYBGNR7JDkMv0u1Wa-V91k5ZuG2eo1xZg%3A1578924657991&sa=1&ei=cXocXq2QPIbr_Qaqq7v4DQ&q=eneloop+discharge+curve&oq=eneloop+discharge+curve&gs_l=img.3..0j0i7i30.9817.12291..12592...0.0..0.836.2439.1j7j5-1j1......0....1..gws-wiz-img.......35i39j0i5i30.eMHVbnejgxY&ved=0ahUKEwjtjPfa4IDnAhWGdd8KHarVDt8Q4dUDCAY&uact=5

The self discharge curve is similar, the Eneloop will loose a decent amount right at first then the discharge will taper off. So after 4 months you might have 90% capacity and then after 12 months it will be 89%.

The other issue I run into is a lot of newer devices will still draw some current even when off for the soft on, or internal close, or internal settings. My old Garmin GPS I've learned to top off the batteries once a month for example.
Posted by: Ratch

Re: Reminder: rechargeables - 01/13/20 11:36 PM

Question: Eneloops May discharge in storage, but after a long period can they be brought back up to serviceable voltage, say by use of a solar charger, etc?
Posted by: hikermor

Re: Reminder: rechargeables - 01/14/20 03:43 AM

I have never had an Eneloops go completely dead on me while in storage, but I have exhausted a few in service. I have charged them right up, both with solar panels and 120 AC.

I keep several NiMHs on hand, nominally fully charged. When I go out on a trip or a project, I pop a few on the charger to be sure they are full. Usually only takes a few minutes.I also routinely carry AA and AAA lithium primary batteries. Each will power my headlamp and my EDC key chain light.

The tendency seems to going toward lights, etc. that are directly rechargeable - no removable batteries at all. You simply plug in the appropriate charging cable.

The day will come when i will take to the field, carrying phone, lights, GPS unit and whatever, along with a power bank and maybe a solar panel. you simply move the electrons around to where you need them. A good many power banks are also adequate flashlights.
Posted by: dougwalkabout

Re: Reminder: rechargeables - 01/14/20 03:10 PM

NiMH batteries also perform best when exercised on occasion. A few full charge and discharge cycles helps restore their full capacity.
Posted by: Russ

Re: Reminder: rechargeables - 01/14/20 04:48 PM

I like replaceable batteries because they are really quick to swap out, but if time is not a factor, the power bank + solar panel option is a good one.