In the Mercedes-Benz E240 1998, the battery is located in the trunk, on the right-hand side.
To access the battery:
1. Open the trunk.
2. Remove the trunk liner.
3. The battery will be located on the right-hand side, behind the spare tire.
Note: The battery in the Mercedes-Benz E240 1998 is a lead-acid battery. It is recommended that you replace the battery every 4-5 years, or as needed.