Charging circuits...

Hi, I am new to this forum.

Am currently looking at how rechargeable batteries are being charged. Could anyone provide any links where I can find more help on such a topic? I am currently looking at a capacitive circuit to charge up a lithium ion battery...

Thanks in advance.

Appleon

**broken link removed**

Maxim have a whole load of application notes complete with circuit diagrams for Li-ion battery chargers, battery managers and combined power-supplies for portable equipment, well worth a look

I am currently looking at a capacitive circuit to charge up a lithium ion battery...

Thanks in advance.

Appleon


What do you mean by that ?

Lion batteries need to be charged in such a way that the current is held constant whilst the charge voltage doesnt rise too abruptly......

Battery voltages below 2.9v/cell require trickle charging at the 0.1C rate until they reach 3.0v/cell when the charge rate may be increased....

A simple circuit based on an LM317 with current limiting circuitry can be used.........

What size packs/cells are you charging ?

Ive never tried charging Li Ion batteries but have tried for nimh and nicd. Like tansis suggested, MAXIM-IC has plenty of information and controller chips used for charging, i used the max713-712 for nimh/nicd and wasnt too hard to make, plenty of diretions and schematics on their datasheets. Also, i believe texasinstruments has some charging chips as does maxim along with fuel guages and such for batteries (i think..??).

Ivan C.

Thanks...

Thanks for the reference, I will look into it further to see what chips are suitable.

I am actually looking at ways of charging up cells via non-conventional means like solar energy conversion and movement-generated power. In this case, I am actually looking at circuits which allows a small current to charge up devices such as rechargeable batteries. I understand that the power generated from such means might not be really significant for simple circuits, hence a need to find out how conventional means work before I can proceed further.

Appleon