Cheap batteries for electric/hybrid bike?

[NiHaoMike]

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It seems like a great deal for 12 1.3Ah high current NiMH cells (I assume, although it would still be a good deal if lead acid). Connect several packs in series for higher voltage and subassemblies in parallel for higher capacity and current rating.

[RobertSmalls]

Some competition:
7Ah sealed lead-acid 12V battery
12V Rechargable Spotlight which I've seen at Ace for ~$10-15, from which I pulled a 7Ah 12V battery for my bicycle's illumination system.

I'd love to know where I can buy a dozen of those batteries at a good price for an electric lawn mower project.

14.4V Power tool batteries: $160/KWh
$15 7AH 12.8V Pb-acid: $167/KWh
Wal-Mart deep-cycle marine battery (obviously unsuitable for a bike): $42/KWh

[Daox]

They're probably NiCds. All the other packs in the "you may be interested in" section that were 14V were NiCds.

They would be reeeeeeeally fun to play with though.

[NiHaoMike]

Looks like they're very good for a beginner hybrid bike. More forgiving than other types of batteries, lighter than lead acid, is cheap, and can handle high current draws. Although it would not be as environmentally friendly as more modern types such as LiFePO4 and NiMH, it is still better than lead acid. In particular, since leaving the batteries partially discharged is fine, it can allow for better regen operation at the start than lead acid.

I wonder how long they'll last with Prius-like battery management...