Any offers on this question?
Yes in the Mustang the NiCad has better starting performance vs the Lead Acid. At the cost of more thermal risk. I have Lead Acid. Also weight is much lower.
Weight? (for easier placement w/i w&b envelope)
Volume? (for easier placement altogether)
Sustained current capacity? (Starting performance, gen out performance)
Maybe the reason is that traditionally NiCd has been used for aviation (military aircraft and airliners). More kWh per kg than lead and can be charged fast.