Worry that charging the battery for a few minutes here and there will shorten the battery life?

I dig a little deeper into the myths of lithium-ion batteries, and this is what I found:

'It is a common myth (and one that I believed until recently) that a battery will live longest if you try and empty the charge completely from it when storing it or before charging it. In fact lithium-ion batteries last longest if they are about 40 per cent full. If you keep two identical batteries for a year at 40 degrees Celsius, one at 40 per cent charge and the other at 100 per cent charge, the first battery will last 20 per cent longer than the second.' (The Test Bed: Prolonging laptop and mobile phone batteries - computer product reviews and news)

'Avoid frequent full discharges because this puts additional strain on the battery. Several partial discharges with frequent recharges are better for lithium-ion than one deep one. Recharging a partially charged lithium-ion does not cause harm because there is no memory.' (How to prolong lithium-based batteries)

• 'Unlike Ni-Cd batteries, lithium-ion batteries should be charged early and often. However, if they are not used for a long time, they should be brought to a charge level of around 40% - 60%. Lithium-ion batteries should never be "deep-cycled" like Ni-Cd batteries.[7]
• Lithium-ion batteries should never be depleted to below their minimum voltage, 2.4v to 3.0v.
• Li-ion batteries should be kept cool. Ideally they are stored in a refrigerator. Aging will take its toll much faster at high temperatures. The high temperatures found in cars cause lithium-ion batteries to degrade rapidly.' (Lithium-ion battery - Wikipedia, the free encyclopedia)