Re: Can alternators charge EV batteries?
Yeah, it's a fairly common question here. Most people don't realize that an alternator puts a pretty strong drag against the engine in a normal car causing it to consume more fuel than if it wasn't there. It doesn't just spin like people think it does.
In order to waste less gas and to produce electricity while in auto-stop, your wife's Accord uses a DC-DC converter and doesn't have an alternator. I don't know if any hybrids do, it is possible that some of the early GM hybrids do but their 36 volt systems don't do much more than engine idle auto-stop anyway and so the GM models never got very popular or much more fuel efficient than other cars as far as I can tell.
For the most part, the idea behind a hybrid is to use a smaller engine so you can keep the engine under a higher load while cruising which gives it better gas mileage. Stopping the engine when it would be idling also can save a significant amount of fuel. The batteries and electric motor(s) in hybrids assist the car to provide extra torque that a smaller engine doesn't have so the driving experience isn't reduced by having a less powerful engine. I like how Honda setup its hybrid drivetrain, it is simple, low cost, and very effective way to do it. I drive a 2000 Insight and love it, and with reasonable mostly highway driving, I get 70+ mpg tanks in the summer and a 1st Gen Insight will be my conversion to electric. I've measured out battery space already and have decided which motor I'd like to fit. I like the Nissan Leaf too but the auto manufacturers could do better in terms of efficiency(my goal) but right now the major manufacturers are aiming for mainstream or slightly higher-end acceptance and I don't blame them which is why I'll convert mine instead of buying what they are selling.