Li-Ion 3.0v vs LifePO4 3.0v & charger questions

LED Flashlights – General Info
1

Hi, I hope somebody could help me. I’m a little confused about battery & charger for my Xtar WK20.
It uses CR123A, and only supports 3.0V (no 3.7V).

I’m looking at Fasttech, and I found :
1. 17335 3.0V 1000mAh Rechargeable Li-ion Batteries (2-Pack)
http://www.fasttech.com/products/1420/10001157/1098400-17335-30v-1000mah-rechargeable-li-ion-batteries-2-
2. UltraFire CR123A / 16340 800mAh 3.0V Rechargeable LiFePO4 Battery (2-Pack)
http://www.fasttech.com/products/0/10002788/1207800-ultrafire-cr123a-16340-800mah-rechargeable-lifepo

Based on size, it seems I can use both. My original Xtar CR123A is actually 1mm taller than both options.
Do I need to care whether I use Li-ion or LifePO4 battery ? Any differences ?

And now the charger.
I’m looking at :
1. UltraFire WF-188 All-in-One Batteries Charger for 3.2 / 3.7V lithium battery charger
http://www.fasttech.com/products/1421/10000857/1073300-ultrafire-wf-188-all-in-one-batteries-charger
2. HuangQao HG-1210W Dual Channels Li-ion / Li-FePO4 Batteries Charger for 3.0V/3.2V/3.6V/3.7V Li-ion/Li-FePO4 rechargeable batteries
http://www.fasttech.com/products/1421/10002586/1208900-huangao-hg-1210w-dual-channels-li-ion-li-fepo4-ba

I have question with the Ulrafire charger. It only says 3.2V lithium. I assume they mean 3.0v lithium ?
Will this charge LifePO4 battery if it does support 3.0v ? or do I specifically need a charger that supports LifePO4 like the Huang Qao ? I wonder if it can be used to charge the two battery options above.

Thanks.

2

If your flashlight says only 3.0V nominal voltage then you want to use only LifePO4. Now both batteries that you linked are LifePO4 based on the 3.0V rating.

3

Either cell should be okay in your light. One of those cells is LiFePO4, but the other (label reads Li-ion) appears to use Li-Co chemistry with a built-in diode to drop the voltage to about 3v. The Li-ion cell would need a normal 4.2 volt charger.

HKJ reviewed a similar cell with a dropping diode.

Either charger would charge either cell, using appropriate settings. LiFePO4 cells have a nominal voltage of about 3.2v but they are charged with 3.6 volts. Labeling for both the cells and compatible chargers is a mixed bag, with 3.0 or 3.2 appearing on the cells and 3.0, 3.2 or 3.6 on compatible chargers.

I use LiFePO4 in my 3.0v lights without problems and prefer them over the li-ion with diode because there is less to go wrong.

4

LiFePO4 is also a safer chemistry, and fewer precautions need to be taken.

5

Thank u. I’ve ordered LifePO4 & HuangQao charger just to be on the safe side.