You're true on all of your points. But there's other factors that make them very interesting. 1. Since the electrolyte is a base (Sodium/Potassium hydroxide) y

You're true on all of your points. But there's other factors that make them very interesting. 1. Since the electrolyte is a base (Sodium/Potassium hydroxide) you can make it out of wood ash in a pinch. 2. The batteries can handle all sorts of catastrophic damage - have a charged battery and run a gutter nail through every plate? It'll fizzle and discharge in the nail. 3. You can severely overcharge and undercharge with no ill effect. Our current NiMH, Lithiums and the like all have really bad effects when you under/over charge them. Blowing up is one such... err, "feature" 4. These batteries are known to last over 100 years. They were some of the first ones that Ford and Edison put in cars. Chalk this up to longevity (and no acid eating consumable lead plates). Oh, and for your electolyte losses- true that you do need to top off with distilled water. But 'regular changing' is actually around 6 months to 1 year. I wouldn't be listing that as a major downside. I'd much rather add a few pellets of NaOH and some distilled every 6 months than pay for a new lead-acid battery every 2-3 years.