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Rechargeable CR2 (3v) Battery Pack for a Digital Harinezumi camera? Answered

I've been burning through CR2 batteries while using my Harinezumi camera. I would like to make a battery pack that wires into battery compartment, makes a connection with the terminals and keeps it juiced as long as the pack can juice it.  

Ideally, I'd like to have the battery pack in my pocket with a wire going to the camera through a small hole drilled in the battery compartment door.

I have about 10 rechargeable CR2 batteries with these specs...
Rechargeable 3V CR2 800mAh
which I've been using to power the camera just fine,,, just not long enough.

How would I go about making a battery pack to give the correct current/power to the camera without causing any harm (frying it)?  Should I use and combine the batteries I already have , or should I make a battery pack with different, bigger, batteries?

Once I figure this out, I'll post the complete instructable on here with photos of my project. Thanks!!!


How many batteries do you put in the camera at a time?

Are they stacked together like coins or do they each have their own slots?

Searching the net as near as I can tell it uses one battery at a time.  If that is so then you can wire as many cr2 batteries in parallel in a pack and not hurt the camera.  The camera will only draw as much current as it needs if the voltage is correct.

Wiring them in parallel will keep them at 1 volt but will be increasing the current available each time.

Make a battery adapter the size and shape of the cr2 and attach your battery lead to that. Then just insert that instead of the cr2.

I had a battery adapter in mind. Just to make sure, is that the parallel circuit you're talking about?

cr2 battery pack.JPG

I think this is the direction I'm looking for. It holds one battery at a time (no jack). So, what you're saying is, I can theoretically have 10 cr2's connected in parallel and then connected to the terminals in the battery compartment and be able to extend the battery life by 10 (safely)?

Exactly. It may not be 10 times the life or it may be 12 times. Different loads do different things to different batteries, but you can expect a huge increase over just using one.

But you have to be very careful to get the polarity right.  Lots of electronic stuff won't have any safeguard against inserting the battery the wrong way and can be zapped instantly.

I am not sure I would approach this problem by altering the battery compartment. Does this camera have a power adapter jack? If so I might try coming up with an external hookup using that jack. You can pick up laptop backpacks with built in solar power supplies for mobile devices that you might be able to adapt. Or to just run a recharger for your batteries in the field. If there is an external power adapter accessory available for this camera, you might try converting it rather than reinventing the wheel.

No jack. Wish it did. All it has is one cr2 which dies unexpectedly and way too soon. So I'm trying to make a pack that just feeds power to the existing terminals, giving me 3,4,5,6 times as much battery life without dealing with switching out batteries.

Get a battery pack that holds two common batteries (AA AAA C or D even) and wire it to the battery terminals. I would use a long tough cord (usb cable?) and have the batteries in my pocket while the camera is in use.