Rechargeable CR123 Batteries

Ben due to the voltage requirements for the CR123 an AA charger wont work. There are actually 2 flavors of rechargeable CR123 batteries, 3.0v or 3.7v. For under $5 shipped you can get a 1.2 oz travel charger. It is extremely important not to overcharge Li-Ion cells so even if you did rig the AA charger for higher voltage, the cells may degrade quickly.

I use the 3.7v version
Here is the 3.0v version

Howdy Bender — thanks for the quick response!

Questions for ye:

1. Will both versions power my Steripen Advneturer properly?

2. Since the voltage is either higher or the same as AA / AAA batteries, there shouldn't be any problem with overcharging, correct? If anything, I am thinking an AA / AAA charger would undercharge a bit (which can still be OK)???

One more question — to anyone who has rechargeable CR123 batteries: Any particular brand that you would recommend (or recommend against)? Thanks in advance.

I've used the Sonshine brand 3.0V rechargables for a few years now in my EDC flashlights (Fenix P2D, Quark Ti, Surefire G2). I thought they were just eBay cheapies, but subsequent reading on the flashlight forums indicates that they are pretty good. I just AC charge them at home, but the charger is pretty compact and small.

Hi Ben,

Overcharging, no, but a charger for 1.2V cells seems unlikely to charge lithium cells at all (they shut down when discharged to somewhere around 2.5-3V) unless the AA charger runs at a higher voltage than the cells it's intended to charge. I'll happily defer to Roger Caffin or a similarly informed electronics expert on that. Here's some "fun" reading on the care and feeding of Li-Ion batteries :-)

http://powerelectronics.com/portable_power_management/battery_charger_ics/804PET22li-ion-battery-life.pdf

On whether one can safely put higher voltage RCR123 cells in a SteriPEN, I'd seek their assurance that there's no potential to overdrive the purifier's electronics with over 7V, before trying. They may have protection built in, but it would be good to have a green light from the maker.

It's doubtful the SteriPEN will cycle reliably with partially charged RCR123 cells, at least with cold water. I've had the Aquastar fail to run with new, generic disposable cells with very cold water.

You might check the battery forum at Candlepower Forums for RCR123 brand suggestions. They're the go-to folks on what's available and especially, the brands to avoid because they might go "boom."

Cheers,

Rick

Ben your AA charger does not put out enough voltage for this. Even if you rewired it in series you probably wouldn't get enough. The Steripen manual I looked at was unclear if 3.7v was ok. AW makes some of the best RCR123 batteries but they get expensive. I am using cheap protected Ultrafires in my flashlight and they are holding up fine. Protected cells are nice because they have a circuit built in to prevent over discharging. Candlepowerforums.com is a great place to look. Of course I think you need to get 4sevens Quark Mini 123 since you will have all these batteries!

Thanks for the additional insights.

I called Steripen, and they recommended that higher (3.7) voltage CR123 rechargeables be used.

Looks to me the potential problem with rigging a charger that charges AA batteries is one of undercharging — and not overcharging. Hmmm… I may be tempted to give it a try.

For those who have used rechargeable CR123's — particularly for Steripen and such — what are your experiences? How do they compare with regular CR123's in the number of treatments you can get per charge? And are you happy with the length of time that the rechargeables stay charged in-between usage?