I’ve raged a lot on my networks about how crap my Apple Magic Mouse battery life has been and how it keeps constantly disconnecting. I would get constant disconnects and I have done research and found one suggesting that the battery contacts were getting bumped so I jammed a piece of paper in there and it appeared that it was doing a better job, for about a week, then back to the old tricks.

To diagnose the problem I wondered if the OS was logging anything. I opened up the Console app to see if the OS was logging anything about the mouse and sure enough it was. I was able to see my mouse disconnect and reconnect in real-time as it logs with entries like this:

11/08/11 8:48:12 AM	kernel	[12a53600][AppleMultitouchHIDEventDriver::start] entered
11/08/11 8:48:12 AM	kernel	[1723e400][AppleMultitouchDevice::start] entered
11/08/11 8:50:04 AM	kernel	[1723e400][AppleMultitouchDevice::willTerminate] entered
11/08/11 8:50:04 AM	kernel	[1723e400][AppleMultitouchDevice::stop] entered

Ok, so it’s disconnecting, what does that mean? I saw these in the logs months ago but googling the error nothing came up. I decided to give it another go today and came across this post on the Apple Discussion Forums.  With its first post in 2009 which is weird cause I didn’t find that in my searches earlier in the year. It’s got 5 pages of people mostly saying ‘I got the same problem’ but one guy sparklelellama suggested it could be the batteries themselves and specifically mentions Duracell batteries and other cheap batteries. He hypothesizes that the magic mouse requires a 1.5V constant power output and that cheaper batteries can’t handle it.

So I decided to give his idea a bit more thought. I pulled out the multimeter and sure enough he was right. A brand new Eveready ‘Super Heavy Duty’ was outputting 1.68 V while one that has been in my magic mouse for a week was only outputting 1.46V after a week of moderate use it dropped 0.24V, that’s massive! Not so super heavy-duty it would seem.

Cheap Batteries

I put some Duracell’s back into the Magic Mouse and the disconnect problems seem to have disappeared. If it changes in a week I’ll report back. Otherwise don’t skimp on your batteries and get the best you can, cause I can finally talk about the magic of the Apple Magic Mouse.

UPDATE:

I’ve purchased an Apple rechargeable battery pack and all my issues with my mouse have gone for good!