Science of batteries

I recently bought what I would consider my first 'serious' bike light: 300 lumens, rechargeable batteries, sears the eyeballs if you stare at it long enough. I had been a satisfied user of the Cateye Opticube which has an obnoxious blinking mode and gets enough attention from vehicles. I also ride with various red blinkies on the sides and back to be visible from all angles.

One of the big differences between the 'serious' bike lights and the blinkies has to do with battery life. The people who make my NiteRider Mini-Newt 300 USB are very aware that generating a high quantity of light sucks power big time. Hence, the battery pack is made of rechargeable Lithium-ion batteries which need to be recharged about every 3 - 4 hours of use. Other manufacturers of rechargeable bike lights have standardized on this type of battery as well.

The great thing is they are easily charged, either by an A/C power adapter or plugging in to a USB port on the computer. However, the obsessive part of me is troubled to learn that there is an optimum cycling of discharge/recharge in order to prolong battery life. Did you know, for example, that you can almost triple the life of your batteries by never discharging them by more than 50% of their capacity? Or, did you know that storing your batteries at 100% of charge for extended periods of time is actually detrimental to overall capacity? Where can one find such great info: at Battery University, of course!
 
I should note that I bike in town, there is lighting in many areas but there are also lots of cars. While I don't usually need to light the trail, I do need to be seen. Because of the brightness of this new light and the fact I can easily recharge I now leave the thing on full. The increased margin of safety certainly seems huge since I find cars anticipating my approach more than trying to cut in front of me. Maybe I am just blinding them!