Howard, You are one of the
Howard, You are one of the NiMH zealots .. you have made your points .. thank you.
However..
1) What Aaron meant by "lower voltage" is that the per-cell voltage of NiMH is 1.2 volts while the per-cell voltage of lithium ion is typically 3.3 volts, but this depends on the specific chemistry. This means a lithium pack requires fewer cells to reach the same voltage, fewer cells means better reliability.
2) shorter lifespan - I don't know enough to comment, other than there are many lithium suppliers claiming 3000 charge cycles. The thundersky's in my car are rated for that number of charge cycles. And, yes, I know many people who own NiMH RAV4 EV's and have had amazingly long useful lifetimes
3) I agree with you that most lithium batteries have a narrow enough temperature range to be a problem. See the concerns over cold weather or hot weather impacts on the Leaf. However, A123 recently developed a variant of their battery that has better temperature range.
4) low shelf life - sounds as if Aaron was referring to the self discharge rate. I don't like AA NIMH cells for my portable gizmos because of this, but a couple years ago found some AA NiMH cells that do not self discharge. That's a good thing. It means that NiMH can be designed to not self discharge.
5/6) Charge and discharge rate is extremely important. The discharge rate governs how fast the vehicle can go, which is very important when merging onto a highway and a big truck is barrelling down on you. The charge rate directly determines the effective speed because it determines how quickly your car recharges while on a trip.