I recently rebuilt my Sharp Mobilon HC-4500
battery. I did it in about 30 minutes, and it was very easy. The OEM rechargeable battery in the Mobilon is a 2.4v 2450mAh NiMH. When I got done, I had a 2.5v 2600NiMH. It works great!
NOTE: I am not responsible for any damage that happens if you attempt this. My rebuilt
battery has been working better than new for 2 months now, so this information is only a synopsis of what I did.
Here's what I used:
- Xacto or similar thin blade knife
- Long, thin screwdriver
- Double-sided foam tape
- Super glue
(optional
)
- Replacement batteries
(I used 2 AA 2600mAh NiMH cells - got a pack of 4 at Microcenter for $6. You can use any AA size NiMH rechargeable batteries, but the higher the "mAh" rating, the longer they'll last between charges. You'll need at least 2450mAh to match the stock
battery pack. Do NOT use NiCad or any other rechargeable types - only Nickel Metal Hydride.
)
Here's how to do it:
1. Remove the
battery pack from the device.
2. Using an Xacto knife, cut along the bottom of the
battery pack where the plastic comes together
(see picture
). You're cutting through the plastic, so don't be too gentle.
3. Get a thin screwdriver & pry the two plastic parts apart
(top half & bottom half
). Look at the polarity of the batteries inside - they follow the same polarity as normal batteries
(flat side is -, the bump is +
. Memorize what polarity goes to which side, so you don't put the new cells in backwards.
4. Remove the old batteries inside, using your screwdriver. You'll have two batteries, connected by a thermal fuse.
5. The batteries you removed are a little thicker than the AA cells you're putting in there. That's where the double sided foam tape comes in. I used the foam tape on the bottom of the
battery holder & on the top, to hold the batteries in place. Cut thin strips of the foam tape & put it in now. Test fit everything by only removing one side of the tape, then put the batteries in & close the lid. The batteries might be a tight fit between the battery clips at the end, but they'll fit.
6. If everything fits, remove the other side of the tape & stick your new batteries in. I chose not to use the thermal fuse in my new setup, and it's been working fine for a couple months. If you choose to use it, you'll have to solder it in place yourself.
7. Put the top of the
battery pack on. When you added foam tape, you should have added it to both sides of the plastic battery case, so when you stick everything together, the foam tape should hold everything together. If you have super glue, you can lay a bead down at the edges of the plastic, to glue the case back together. I didn't & mine works fine, but there's no harm in a little super glue
(make sure you clamp the pack together if you glue
).
8. Stick your new
battery pack in your HPC. Plug the charger into the handheld & into the wall. If you did everything right, the "charging" light on the handheld should come on & your device should power on when you're done charging.
