By Adriana Zwink • Difficulty: Moderate
Follow this guide to replace a worn-out or dead battery in your MX Ergo wireless mouse.
It’s natural for batteries to lose capacity as they age. If your mouse dies quickly and doesn't hold a charge, it may be time to replace the battery.
For safety, perform this repair when your battery is below 15% charge. Any charged lithium-ion battery can be hazardous if punctured or damaged. If your battery looks puffy or swollen, take appropriate precautions.
- Before you begin, flip the mouse's power switch into the OFF position.
- Unplug all cables from your mouse.
- Remove the magnetic cover by pulling it away from the bottom of your mouse.
- Use a Torx T6 screwdriver to remove the six 5.7 mm-long screws securing the two halves of the mouse together.
- Insert a spudger into the hole on the bottom of the mouse, beneath the trackball.
- Use the spudger to push the trackball out of its recess.
- Remove the trackball.
- Insert the tip of an opening pick into the seam between the two halves, near the middle of the right edge.
- Twist the opening pick to release the plastic clip.
- Slide the opening pick along the seam until it's about half way to the rear of the mouse.
- Twist the pick to release the plastic clip.
- Slide the opening pick all the way to the rear the mouse.
- Twist the pick to release the plastic clip.
- Slide the opening pick to the middle of the left edge, next to the trackball recess.
- Twist the pick to release the plastic clip.
- Gently lift the top half and place it to the left of the mouse so you can access the internals.
- Use the point of a spudger to gently lift alternating sides of the black sliding lock on the interconnect cable socket.
- Use tweezers or your fingers to pull the interconnect cable straight up and out of its socket.
- Lift the top half of the mouse straight up and remove it.
- Use the pointed end of a spudger to push up and the battery connector, loosening it in its socket.
- Insert the long edge of an opening pick between the long edge of the battery and its housing, at the side opposite the battery cable.
- Use your opening pick to pry up the battery and separate its adhesive. Apply steady, constant force and slide the pick farther under the battery as necessary.
- Use your fingers to lift the battery out of its housing.
- Use your fingers to grip the battery cables and pull the connector straight up and out of its socket.
- Remove the battery.
- If the battery adhesive is still sticky, you can reuse it. Otherwise, remove all the old battery adhesive.
- If your new battery has adhesive pre-installed, remove the plastic liner to expose the adhesive. Otherwise, apply strips of thin, double-sided tape to the battery well (not directly to the battery) where the old adhesive was.
- Firmly press the battery into place, making sure the cables are on the side closest to their socket.
Compare your new replacement part to the original part—you may need to transfer remaining components or remove adhesive backings from the new part before you install it.
To reassemble your device, follow these instructions in reverse order.
Repair didn’t go as planned? Try some basic troubleshooting, or ask our Answers community for help.
Reuse or Recycle—Never put discarded electronic parts in household waste. Visit Logitech Recycling to find your nearest recycling points, including the option to mail back old devices to Logitech for free if there’s no convenient solution in your area. You can also take your e-waste to any R2 or e-Stewards certified recycler. And don’t let good working parts or repaired devices die a slow death in your sock drawer—pass them along to someone who can use them.
Share your experience—Leave a comment here or send your feedback directly to Logitech at repair@logitech.com to help shape future repair guides and product design.