LiFePO4 batteries

[Tjin]

Has anybody have any experians with LiFePO4 batteries? I have seen them popping up on several site's:

http://www.all-battery.com/index.asp?PageAction=VIEWPROD&ProdID=1877
http://batteryjunction.com/2rc375reliba.html
http://www.e-lectronics.net/cr123a-lifepo4-rechargeable-volt-p-146.html

Although they are lower in capacity, there voltage are closer to primiary lithiums and are claimed to be very safe.

 

[AndyTiedye]

I have used some of AW's LiFePO4's.

They seem to have about 500mah capacity.

Charge on an Ultrafire WF-138 in the "3.0v" position.

 

[edc3]

I bought a pair of AW's and a charger to play with. I charged them up and got around 35 minutes of runtime on a Wolf-Eyes Sniper with HO Cree. It doesn't seem like much, but in real life usage I can go three or four days between charges. Although I feel pretty comfortable using protected [SIZE=-1]Li-ion I [/SIZE]like the peace of mind in charging and using these cells. According to what I've read they will not vent or explode. See AW's sales thread here for more info.

 

[TorchBoy]

Some more offerings I saw recently (added a day or two ago):

18650 pair: https://www.kaidomain.com/WEBUI/ProductDetail.aspx?TranID=2867
14500 (AA) pair: https://www.kaidomain.com/WEBUI/ProductDetail.aspx?TranID=2868
RCR123A pair: https://www.kaidomain.com/WEBUI/ProductDetail.aspx?TranID=2869

I'm glad this sort is becoming more common as I've heard it's much safer. I can't remember if they need a special charger.

 

[Fallingwater]

The kaidomain cells seem good.
I'd like to get some to experiment, but the lower voltage is a problem for devices expecting normal LiIon cells.

On the other hand, gadgets that use two AAs in series could be rewired to use two LiFe 14500s in parallel...

 

[Northernflame]

INQUIRY:

I too noticed the KaiD lipo **14500** I'm interested in buying a few.

https://www.kaidomain.com/WEBUI/ProductDetail.aspx?TranID=2868

My first questions is. Can the Ultrafire/Darin wf-139 charger charge these 3vdc lipo's? Safely.

I've heard rumors that a special charger is needed. Unfortunately there is little data (white papers) on the charging requirements of li-pos.

I use currently 14500 li-ions (3.7vDC) 1Xli-ion + a dummy battery with a resistance in an ex: ultrafire-606A FL and it's wonderous.

My main question about the LI-POs is if they would give any better runtime (1li-po cell) over a 2xAA nimh @ 2000mah each setup (averaged out common ni-mh)?

Last question: Would it be safe to run a single 14500 LI-PO in a single AA FL?

Thanks.

 

[jeremyison05]

So could you safely run these in Incan lights like a SF 6P with stock bulbs and not instaflash them or reduce the life of the bulb? If so this will be a great rechargeable solution for "stock" lights.

 

[Northernflame]

So could you safely run these in Incan lights like a SF 6P with stock bulbs and not instaflash them or reduce the life of the bulb? If so this will be a great rechargeable solution for "stock" lights.

Hi.

Based on the limited specs on lipos (why does that sound like a medical procedure Heh, they sucked (liposuc...) the extra fat out of the li-ion to make a li-po... OK you can groan now .

LI-POs have a lower discharge rate. However they have a very smooth and safe flow rate. This is why sony and others are switching thier li-ion's for li-po (after that li-ion distaster Sony underwent).

I would be concerned if you used 14500-18670 "li-ions" in your sf-6p without some form of resistance.

I've ordered a few of the li-po 14500's . From the tech specs i should no longer need a resistance in my 2xAA FL, that was needed when li-ions were used.

Thanks

 

[TorchBoy]

LI-POs have a lower discharge rate. However they have a very smooth and safe flow rate.

Do you mean LiFePOs? (With or without the 4.) Your mention of safety implies yes. So do you mean a lower self discharge rate? LiFePOs have a higher discharge rate. Wikipedia:

LiFePO4 cells have higher discharge current, do not explode under extreme conditions and weigh less, but have lower voltage and energy density than normal Li-ion cells.

 

[jrv]

I don't see any chargers for these batteries on the Kai site so you're probably going to have to use magnets & wires with the 3v 123 chargers.

 

[protein_man]

If you live in Australia you can get them cheap here found them while doing a search. It looks like they put the real capacity on them, not an exaggerated one!

These things would be awesome for a bike light battery pack, it would be great if somebody made 18650 battery holders for such applications!

 

[Northernflame]

I don't see any chargers for these batteries on the Kai site so you're probably going to have to use magnets & wires with the 3v 123 chargers.

According to the specs the manf provided the 14500 li-po kai sells are identicle to AA alkalines in form. Therefore no magnets required.

I'l provide a review when my order comes in.

 

[TorchBoy]

According to the specs the manf provided the 14500 li-po kai sells are identicle to AA alkalines in form.

Now, you don't mean lithium ion polymer, do you?

 

[musicalfruit]

So what can you use to charge these batteries?

Also, are these batteries shorter than Li-Ion 14500s? The AW 14500 that I have seems a touch longer than my Eneloops so my L1D can't go into turbo mode when the 14500 is in there.

Thanks.

 

[Fallingwater]

So what can you use to charge these batteries?

RC charger meant for A123 cells will charge them.
You can also probably use chargers meant for regulated LiIons; the voltage specs are very similar.

 

[jrv]

To stress what TorchBoy said:

LiFePOs are not the same as Li-Po!

Moreover, LiFePO batteries have a nominal voltage of 3.2v, quite a bit lower than Li-Ion's 3.7v. You can't charge a LiFePO in a Li-ion charger (there is one RCR123 charger that has a 3v switch and can be used for 123-size cells, otherwise you're the world of exotic RC chargers).

Expect to get half of the Li-ion capacity in a LiFePO of the same size.

 

[AndyTiedye]

I use LiFePO4's in lights that don't like the Li ion voltage
(if replacing 2xCR123 with 1x17670 is not an option).

 

[jbierling]

Do LiFePO4 batteries need to be protected from overcharging and deep discharging? If so, are they available as protected cells? I've only seen what I think are unprotected ones.

I've read that they are resistant to overcharging, but I haven't seen a reference to the possible dangers of over discharging.

Can LiFePO4 cells be used in series without protection circuits (like nimh), or do they need to be protected like normal Li-ion packs?

-Joel

 

[LA OZ]

I have received 3 sets from Kai today. I ran the first set without first charge, It measured 3.33V on my multimeter. In my A2, it lasted 20min on incan and start flashing. I took it off and check the voltage. It reads 2.8V and kai mentioned that it is safe to discharge to 2V. I am in a process of charging up the first set and ran Gladius on the 2nd set.

Edited
It lasted 40min on the Gladius and the end voltage read 2.7V.

 

[jrv]

I don't think the LiFePO4's have any undercurrent protection so it's not obvious to me why the lights cut out - do these lights cut out with Li-ion too?

Which size cells are these, and how are you charging them? I order a pair of 18650 LiFePO4 and am wondering how to verify they really are LiFePO4 and not low-capacity unprotected Li-ion. I intend to charge them with a Triton.

PS. Oops - I don't think Triton has a LiFePO4 program