On Tue, Oct 14, 2014 at 10:14 PM, ChemE Stewart <[email protected]> wrote: > Or just ride your bike... > > http://koin.com/2014/09/05/electric-bike-battery-may-have-caused-bend-house-fire/
I have been studying the 18650, the cell which powers the Tesla. Proper charging of the cell is a far cry from slapping the old trickle charger on the '64 Chev Impala. There are three stages in the charge cycle: http://www.electronicproducts.com/Power_Products/Challenges_in_Li-ion_charging.aspx For your multi-cell laptop battery, there is a 4th stage between the CC and CV stages called cell equalization. Due to variations in the internal resistance of each cell, cells in series will not charge evenly. Your 11.1 V (nom) laptop battery can separately charge each 3.7 V parallel stage. The fully charged laptop will actually read about 4.2 V per cell. It is considered fully discharged at about 2.8 V. Optimum life is achieved by always charging between 25 and 50% discharge. This kid has a series of videos where he builds his homemade electric bike. This is in the middle of the series where he gets into the 18650: https://www.youtube.com/watch?v=Z-VLdE6RxYQ Tesla Motors and Panasonic are building a plant to produce 35,000,000 18650s by 2018 to the tune of $5,000,000,000 capital cost.
