IanG on Tap

Ian Griffiths in Weblog Form (RSS 2.0)

Blog Navigation

April (2018)

(1 item)

August (2014)

(1 item)

July (2014)

(5 items)

April (2014)

(1 item)

March (2014)

(1 item)

January (2014)

(2 items)

November (2013)

(2 items)

July (2013)

(4 items)

April (2013)

(1 item)

February (2013)

(6 items)

September (2011)

(2 items)

November (2010)

(4 items)

September (2010)

(1 item)

August (2010)

(4 items)

July (2010)

(2 items)

September (2009)

(1 item)

June (2009)

(1 item)

April (2009)

(1 item)

November (2008)

(1 item)

October (2008)

(1 item)

September (2008)

(1 item)

July (2008)

(1 item)

June (2008)

(1 item)

May (2008)

(2 items)

April (2008)

(2 items)

March (2008)

(5 items)

January (2008)

(3 items)

December (2007)

(1 item)

November (2007)

(1 item)

October (2007)

(1 item)

September (2007)

(3 items)

August (2007)

(1 item)

July (2007)

(1 item)

June (2007)

(2 items)

May (2007)

(8 items)

April (2007)

(2 items)

March (2007)

(7 items)

February (2007)

(2 items)

January (2007)

(2 items)

November (2006)

(1 item)

October (2006)

(2 items)

September (2006)

(1 item)

June (2006)

(2 items)

May (2006)

(4 items)

April (2006)

(1 item)

March (2006)

(5 items)

January (2006)

(1 item)

December (2005)

(3 items)

November (2005)

(2 items)

October (2005)

(2 items)

September (2005)

(8 items)

August (2005)

(7 items)

June (2005)

(3 items)

May (2005)

(7 items)

April (2005)

(6 items)

March (2005)

(1 item)

February (2005)

(2 items)

January (2005)

(5 items)

December (2004)

(5 items)

November (2004)

(7 items)

October (2004)

(3 items)

September (2004)

(7 items)

August (2004)

(16 items)

July (2004)

(10 items)

June (2004)

(27 items)

May (2004)

(15 items)

April (2004)

(15 items)

March (2004)

(13 items)

February (2004)

(16 items)

January (2004)

(15 items)

Blog Home

RSS 2.0

Writing

Programming C# 5.0

Programming WPF

Other Sites

Interact Software

NiMH vs Alkaline Batteries (yes, yet another Bluetooth Mouse post)

Wednesday 23 June, 2004, 12:03 AM

A few people have kindly emailed me in response to my ongoing Bluetooth Mouse rambling to make some suggestions about why Microsoft recommend not using rechargeable batteries.

NiMH AA cells have, I'm told, significantly different power output characteristics from Alkaline batteries. They are rated at a lower voltage - nominally 1.2V rather than 1.5V. However, NiMH cells tend to give out 1.2V for almost all of the discharge cycle, dropping off only towards the end, while Alkaline cells tail off gradually throughout their whole life. So in practice, you only get 1.5V from a fresh alkaline cell.

This suggests a couple of reasons why the instructions might tell you not to use rechargeable batteries. The obvious one would be that the mouse might not be able to run on 2.4V (two NiMH batteries). However, empirical evidence suggests otherwise... Another possibility is that the battery charge level circuitry in the mouse will have a hard time predicting when NiMH batteries will go flat because of their sudden end-of-charge drop off as compared to the gradual death of an alkaline cell. That's plausible, but the battery level indicator is already only marginally better than useless, so I'm not too concerned about that one.

Unsurprisingly, the NiMH batteries are still going strong after all of 1 day's use... You'll doubtless be unsurprised to learn that I'll keep you updated as and when more mind-bogglingly exciting mouse battery news breaks.

Copyright © 2002-2013, Interact Software Ltd. Content by Ian Griffiths. Please direct all Web site inquiries to webmaster@interact-sw.co.uk