Using solar cell AA 3.2v LiFePO4 cell for 2 AA alkalines?

[dnix71]

I just bought a pair of 3.2v lipos intended for solar landscape lighting from Radio Shack to see if they would work in my Canon camera. I made a dummy battery/sabot from an old AA nicad and the camera booted and reported 100% battery power. The cells at RS are $10 for a pair and are labelled 600 mah.

Radio Shack doesn't sell a charger. Using a solar light seemed like a slow way to recharge, so I ordered a charger, extra batteries and sabots from eBay-China.

Does anyone here know why this isn't more common, other than you have to remember to use a sabot and not 2 live cells?

This camera and other Canons I owned are/were power hogs and the local AA batteries never lasted very long. A pair of NiMH AA's have plenty of current but the voltage is quite a bit lower than the camera was intended to run on. I also own the mains power switch-mode brick made for the camera for extended shooting indoors. It puts out 3.2v also.

[Harold in CR]

 Any links or photos ? I went to ebay and found nothing. Google sent me to the Wiki where I found description but no photo ?

 I have a Camera power hog, also.  Thanks

[dnix71]

http://www.ebay.com/itm/Coolook-LiFePO4-battery-4-AA-cells-w-dedicated-quick-charger-dummies-/251212484208?pt=US_Rechargeable_Batteries&hash=item3a7d6e4e70

Charger, batteries and dummy cells as a package. I didn't buy this one, but something like it. Radio Shack sells the #14500 cells in a 2 pack, but for some reason the package doesn't have a RS part number or even their name.

https://www.radioshack.com/product/index.jsp?productId=15549636 There are higher capacity cells advertised on eBay, but 600mah is the standard for individual solar landscape lights. As far as I can tell, they are exactly the same dimensions as a standard AA cell, just different chemistry.

[Harold in CR]

 Thanks. Appreciate the links.

 I hate to appear so dumb, but, I have a Konica Dimage camera that takes 4 AA's. How do I figure where - how to use the dummy cells, or do I need them ??  I'm thinking to use 1 cell + and the other cell-, so, why dummy cells ??

 I hate to experiment on a $300.00 camera 

 Thanks again.

[dnix71]

You have to know how the AA's are used in that camera. You will need dummy cells unless the camera runs from 1.5v, which is very unlikely. If the camera uses 6v then you need 2 dummy cells.

If it's this Konica, the external power adapter is 6v, so you need 2 live cells and 2 dummies
http://www.steves-digicams.com/camera-reviews/konica/minolta-dimage-z3/konica-minolta-dimage-z3-review.html

[Bruce S]

Harold;
Each of those AAs are 3.2 instead of 1.5 hench the need for the dummy cell. 4 AAs depending on the configuration would be about 6.0v you only need 2 of these :-)
I'd hate to see you blow out a 300.00 camera too!
Bruce S

[Harold in CR]

 Yes, I'm aware of the voltages. Yes, that is the camera.

 I guess I would need to do some serious checking to figure out where the cells would go.
 + -   -
      +    Is the layout.  Looks like the first + cell and the last - cell would be 6V, but, I will try to use the VOM and check things out.

  Thanks guys.   It's hell getting old and feeble minded.
 

[dnix71]

The dummy cells are just straight wires inside. All you need to do is substitute 2 and 2, it doesn't matter the order as long as the live cells are inserted with their polarity in the usual way. The 2 live cells make 6v, the other two just complete the circuit.

[Harold in CR]

    I thought that through, sometime last night, while sleeping.  Maybe I should take and stay on sleeping pills. I see things much clearer that way. 

 Thanks

[independent]

Hello. The w/kg is such an advantage with lipo but their charging profile is so specific. They are a dangerous formulation and can go into thermal runaway. 4.2v is considered a safe voltage to charge to, 4.23v good with good gear. 4.3v is dangerous and unsafe as I understand it. So most lipo multi-cell batteries monitor each battery for balance for this reason and have safety shutoff features ie electronics in a laptop battery. Also, cycle life is so so, 300 to 350 cycles (from memory) compared to NiMH which is commonly 1000 with most brand name LSD (Low Self Discharge) and 1500 with eneloops.  Those NiMH cycle tests would kill a lipo cell really quick as they are full to dead flat with a 20min break at one end of the cycle. But lipo can discharge the amps and is light and stores more for the same weight but is dangerous HTH

[dnix71]

These are single cells, of the lithium iron phospate type, rather than the organic flammable batteries. The camera won't charge batteries in it anyway, so if something went wrong it would happen in the charger.  Organic lithium batteries are trouble beyond cell phone size. That's the type that burned Boeing. A 65 block of oranic lithium batteries on a plane is death waiting for a chance.