The battery that powers an iSIC data logger is user-replaceable.
1. Disconnect the fastons from the battery terminals inside the iSIC.
2. Remove the two screws on the battery plate with a #3 Phillips head screwdriver. Store the battery plate and screws.
3. Remove the old battery and put the new battery in its place.
4. Connect the fastons to the new battery.
Note: The green LED light on the Analog strip should flash for 10-20 seconds, indicating that the iSIC is receiving power.
5. Secure the battery plate back in place using the plate and screws removed in Step 2.