Discharging Li-Ion batteries

[pier1]

Hello,

I work with some stand alone battery chargers for a project. I have some doubts on the discharge part of the Li-Ion battery.
Generally we disconnect the battery from the load based on voltage sensing. My doubt is that

Is there a concept called as current sensing also in the discharge mode ?

For example: like a battery is only allowed to discharge for a defined time in this current and this could help in increasing the life time of the battery ?

I just happened to hear this from somewhere and am not so sure if this is correct. I googled around a lot and still not arrived at a conclusion  ???

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In the charging mode we generally look at the current rather than the voltage to cut off charging process.

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If any of you came across this topic, Please share your experience.

regards,
Pier

 

[audioguru2]

The load on a rechargeable lithium battery cell must be disconnected when the voltage drops to 3.0V. The battery cell will be damaged and might catch on fire when charged if its voltage is below 3.0V. The battery cell will last longer if the low voltage limit is higher, maybe 3.2V.

Discharge current has nothing to do with it but if the discharge current is too high then the cell will be damaged.

An ordinary rechargeable lithium cell is fully charged at 4.20V and when the charging current drops to about 0.04C. It will catch on fire if charged to a voltage higher than 4.20V. The cell will last longer if charged to only 4.0V.
Newer Ferrous-Lithium cells have a lower maximum charging voltage.