Calculating amp-hours

[Wonderboy]

After Ben's purchase of a ford escape hybrid battery pack on the cheap from ebay, I've recently been considering buying a hybrid battery pack to use for my pure EV conversion. Most hybrid battery packs are way over the voltage I'll need for my application... however the amp-hour rating is far lower. How does putting half the cells in a hybrid pack (or any pack, for that matter) in series affect the amp-hour rating? If I were to take a 144v pack for example and make it into a 72v pack, would its amp-hour rating increase and how much? I'm just brainstorming on how I could make a NiMH pack for cheaper and with comparable amp-hours to a bunch of lead-acid deep cycle batteries at the same voltage.

[baddriver]

Connecting Batteries in Series or Parallel