charge NiMH 3.6 350 mA battery

oslinux23@yahoo.gr

New Member

• Jul 18, 2008

• #1

Hello I want to charge a NiMH 3.6 350 mA battery and I want to find a circuit 220 V (AC) to charge the battery

 

S

ste5442

New Member

• Jul 18, 2008

• #2

Hi,

A company called Linear Technology (linear.com) do a range of off-the-shelf charger IC's - most NiMH charger ICs only require a couple of extra components and could easily be bodged into an existing wall-wart type power supply enclosure.
Please note that I dont think you will find (an IC) one with 220VAC input and charger output ;-)
There are some good app note on the Maxim website about battery charging as well.

Good luck with it!

S.

 

P

picbits

Well-Known Member

• Jul 18, 2008

• #3

Wall wart to convert it down to somewhere around 7-9 volts then an LM317 running in current limiting mode to provide a 35ma constant current charge.

 

audioguru

Well-Known Member

Most Helpful Member

• Jul 18, 2008

• #4

Energizer and other battery manufacturers recommend using a trickle charge current no more than C/40 which is only 8.75mA for this tiny battery.
You need a battery charger IC to detect when the battery is fully charged then swith off the chearger or switch to a low trickle charge current.

The battery charger IC will be able to charge quicker than all night long.

 

B

Boomslang

Member

• Jul 18, 2008

• #5

Just get a cheap nokia phone charger, put 2 of the batteries you want to charge in series and your'e done. The charging current might be a bit high, but I've used it many times (and if your'e not worried that you will not get a 1000 recharges from it). Just note it will not stop charging when the batteries are full.
Do not play around with 220V.

 

audioguru

Well-Known Member

Most Helpful Member

• Jul 18, 2008

• #6

A Ni-MH battery charger knows when the battery is full and turns off the charging.
A Nokia power supply is made to feed the lithium charger circuit in a cell phone and will overcharge a Ni-MH battery.

 

B

Boomslang

Member

• Jul 18, 2008

• #7

I should have added: OLD Nokia charger from a second hand shop. IE: 5110 charger. Sorry. As far as I can tell it does not stop charging when the battery is full... never tested it.

 

S

ste5442

New Member

• Jul 20, 2008

• #8

Most of the newer phones I have dealt with power a charger IC which is inside the phone.
Do the older phone power supplies have a charger IC built in?

 

audioguru

Well-Known Member

Most Helpful Member

• Jul 20, 2008

• #9

We should be talking about apower supply for a phone, not a charger.

If you want to charge a battery properly then you need a power supply and a charger circuit.