锂离子电池进行高效率的充电简介

如何对锂离子电池进行高效率的充电（二）
Low Cost Standalone Linear Battery Charger
Many IC manufacturers are responding to the market need for more accurate
and safer battery charge by developing low-cost linear battery chargers for
low-power portable equipment. Figure 2 shows a low cost standalone linear
battery charger circuit that uses few external components.
[pic]
Figure 2: Low cost standalone linear battery charger diagram

The charger simply drops the adapter’s DC voltage down to the battery
voltage. The power dissipation across the pass element equals adapter
voltage minus the battery voltage times the charge current, which is given
by

[pic]

If a 5-V adapter is used to charge a 1200-mAh or 2200-mAh single cell Li-
Ion battery, Figure 3 shows its power dissipation with 0.7 C rate fast-
ch