Charging the EFL700A39

AN4085

4/16

DocID023052 Rev 2

2

Charging the EFL700A39

2.1

Charging voltage

The EFL700A39 can be easily charged from a 4.2 V ±1% constant voltage source with or

without current limit. More than 90% of the total capacity is recharged when the charge

current falls below 100 µA. For better life duration it is recommended to limit the charge

voltage between 4.0 V and 4.2 V.

2.2

Charging current

A constant current charge is possible provided the maximum charge voltage does not

exceed 4.2 V.

Switch-mode, pulse-mode or linear battery charger devices can be used to secure the

maximum battery charge voltage.

2.3

Charging temperature

The higher the ambient temperature is, the faster the charge is but meanwhile the faster is

the aging of the EFL700A39.

The Figure 2 shows the typical curve of the charge capacity versus the charge time duration

for a 30 °C ambient temperature. As shown in this figure, the EFL700A39 can be recharged

from 0% State-of-Charge (SoC) up to 80% SoC in 20 minutes.

Figure 2. ELF700A39 typical charge curve