You seem to have an obvious battery bias.In my professional life, I was the engineer responsible for batteries on three different projects, spanning the time from 1991 to 2008. The first project used a battery pack filled with NiCad rechargeables (20 ea of super-sub-C size, packed in a shrinkwrap 5x2x2 tube along with overtemperature and overcurrent cutout devices and a 9-pin connector).
The next project was for a light-weight device, and the specification had a requirement to use primary (non-rechargeable) batteries that were readily available on the commercial market. I went to Wal-Mart and bought a large number of lithium camera batteries, 12 of which packed into our custom battery holder were adequate to run the equipment for the time specified.
The last project was to equip soldiers and military equipment and vehicles with portable computer/radios. The batteries for the soldier units were specified as limited to certain types of primary lithium batteries - apparently the Army customer had a lot of them in storage.
With respect to the question on the table - Lithium batteries (on average over the many types) present less of a ccradle-to-grave environmental hazard than NiCad batteries (or the Nickel-Metal Hydride cells that followed). The worst of all is the Lead-Acid type as used in cars - its inherently poisonous nature is mitigated to a large degree by a robust recycling market, driven by strict government regulations.
Have you considered the limited resource nature, and environmental damage of massive lithium mining?
(not to mention disposal)