I found this article on MSNBC the other day. It seems the automakers are trying to perfect more powerfull lithium-ion batteries for use in hybrids and EVs. Could such an advance with LI-Ion bateries also mean more powerfull Green Goats and/or GENSETS suitable for mainline use?
The thought of lithium ion batteries in something that’s subject to so much potential G-force as a car or SUV scares the hell out of me. Li-Ion batteries have two weaknesses - heat and shock. If you’ve ever seen those pictures or movies of exploding laptops, you will understand where I am on this issue.
The sheer amount of Li-Ion batteries needed for a locomotive (any locomotive, Green Goats included) amplify this concern by a magnitude.
If the battery manufacturers can come up with a Li-Ion battery that does not explode if heated beyond 190 degrees F or subjected to 6g, then I would be for it. Until that, I am against it.
My understanding is that GE is working on using sodium sulfur batteries for their hybrid locomotives (and tugboat power plants, and???). The sodium sulfur battery has a slightly lower energy density than Li-ion and probably has a siginificantly lower power density than Li-ion.
There’s also some work being done on Li batteries using phosphates instead of cobalt, these batteries are MUCH less likely to self-destruct in the manner of Li-ion batteries. The trade-off is a lower energy density.
One big hold-up with virtually all battery technologies is cycle life, i.e. how many charge discharge cycles can be applied to the battery before it wears out. The trick used on hybrid cars is to severely limit that depth of discharge, so that the battery is allowed to provide maybe 5% of its peak capacity.
Albuquerque, NM, Journal , Monday 9 June 2008, Page 1, Columns 5 & 6, “New Batteries Put to the Test.” Article is about a laboratory at Sandia National Lab that specializes in testing LiOn battery technology, studying what happens when such devices are intentionally short-circuited, heated to high temperature, crushed, etc.
Article is mainly about batteries for automobile use; nothing about use in railway applications–but that does not mean that such research might not be underway or be undertaken in the future at Sandia.