Battery Replacement
Replacing the tomtom1 battery has its challenges.
I bought a replacement battery from RadioShack, catalog number 55026605 for $26 + S&H. It's manufactured by Dantona, model PDA-192LI.
You will also need a T8 torx driver. I purchased a mulit-function driver from my local hardware store (Lowes) manufactured by General, known as the "UltraTech Tool System" for about $18.
Disassembly:
1. Remove the SD chip from the device.
2. Remove the four T8 screws from the rear of the tomtom1.
3. Read though this step in its entirety... this is important reference information.
A. The tomtom1 unit is going to separate into two pieces, the front part (FP) is silver and the back part (BP) is dark grey.
B. The FP contains 98% of the electronics and the screen.
C. The BP hosts the speaker and battery.
D. The speaker and battery are connected to the FP via wire and miniture connectors.
E. You will note that the external antenna connector (BP, upper right corner) is flush with the BP surface.
F. You will also note that the miniture D-connector on the unit (BP, bottom) is also flush with the BP surface.
G. The BP is not removed by applying forces perpendicular to the face of the FP, rather the BP and FP are separated at the top and then the FP is lifted upward with respect to the BP.
4. Now that you have read all the steps in "3" above, separate the unit at the top about 5-10mm, ensure the sides of the BP clear the FP and then lift the FP away from the BP at an angle.
5. It is easier to manage the next steps if you disconnect the wires that link the the FP to the BP.
6. The battery is held in place by adhesive. Removing the battery is, IMHO, the most challenging part of this exercise. The original battery has a shrink-wrapped outer jacket (shiny black in color), and is held in place by a double-sided adhesive tape. I used a box-cutter to cut an incision along the corner of the jacket and then "popped" the battery out of the shrink-wrap. I then used a pair of pliers to grab the shrink-wrap and "tear" is away from the adhesive material. I removed the adhesive tape by scrapping it away with a bamboo skewer from the kitchen. Exercise caution and patience with the box-cutter, restricting your cut to only the shrink-wrap. Remember, a battery contains chemicals and you do not want them getting outside of the designed container.
7. Following successful removal, I put my new battery in the unit, and used a small dab of rubber cement to hold it in place.
As you can read, this procedure is very similiar to others that have been written in this thread.