GunnerAsch wrote:
On Fri, 22 Mar 2013 09:23:17 -0000, "Keith W"
wrote:


The conventional Batteries are sometimes called Sealed Lead Acid
Batteries but they are actually AGM batteries.

Modern passenger aircraft normally use Nickel Cadmium batteries

Why havent they converted over to NmH?

They have a relatively high self discharge rate and can lose
up to 20% of the energy stored in the first 24 hours. This is
acceptable for hybrid vehicles where the battery is primarily a
temporary buffer to capture the energy from regenerative
braking but not good for a system intended to initiate an
aircraft startup sequence after a week in the hangar.

Keith