The charge current on the i4 is a little high, but there's a trick that you can do to lower it;
http://lygte-info.dk/review/Review%20Charger%20Nitecore%20Intellicharger%20i4%20UK.html said:
This brings me around to the trick that can be used when charging small LiIon batteries: Simply put a NiMH battery in the other slot, it does not really matter if it is full or empty (A old worn out NiMH is perfect).
I.e. to charge a small LiIon in slot #1, put a NiMH in slot 3.
I.e. to charge a small LiIon in slot #2, put a NiMH in slot 4.
Eneloops are stellar aren't they? I think they're one of the most important advances in battery technology in a long time.
The Self Discharge of Li-Ion cells is very low, as they don't really "self discharge", the charge that the cells lose when stored is actually the cells losing absolute capacity. Li-Ion cells lose capacity when; Left fully charged for prolonged periods (1 month+), left fully discharged (12 hours+), prolonged high temperatures (40C+) and lastly, being over-charged (~3% per 0.1v!

). As you can see, they're temperamental buggers!
For Long-term storage, Li-Ion cells should be "Storaged", which involves charging/discharging them to a resting voltage of between 3.7 to 3.75 volts (or a charge capacity of ~30%). Fancy chargers have this functionality built in.
For the "under the seat" situation that you describe, regular CR123A lithium primary (non-rechargeable) cells are ideal as they're insensitive to temperature change and have a ten-year shelf-life.
As for your work-light, I believe that the LED floodlights actually work pretty well, one of the 30W ones should make an excellent task-light, especially if colour temperature and accuracy isn't important

That said, when I'm doing mechanical stuff for prolonged periods of time, nothing really beats a good old incandescent halogen floodlight
