Charging Algorithm for Sealed Lead Acid Battery

[devonsc]

bq2031 boost converter

Hi there,

Would like to get some advice if you guys dont mind, regarding charging the sealed lead acid battery.

I'm trying to charge a 12V SLA battery with a boost circuit. Is the following control algorithm good enough? Advice and comments needed.

a.) Disconnect the connection between the boost circuit and the battery. By turning ON the MOSFET to prevent the flow of current to the battery. Then I measure the battery voltage level. If the battery voltage level is lower than 14V. I call the appropriate PWM to charge. Else I dont charge.

b.) After every 2 minutes, I stop charging, disconnect the connection between the battery and the boost circuit by turning ON the MOSFET again. Then, I measure the battery voltage level again. If it is 14V, I stop charging. Else continue.

Is this considered as a constant voltage charging algorithm? Is this all right to be implemented? Thanks in advance. Advice needed.

 

[e_eja]

your circuit called buck converter in oerder to maintain votage at constant you need ome feedback sensor to determain PWM pulse of your swtch

 

[devonsc]

Hi there, isn't the attached circuit a boost converter? Just asking for confirmation.

Apart from that, would like to ask if the mentioned charging control algorithm alright in charging a SLA battery. Lets say if I were to ignore the method called "constant voltage method" for charging purposes.

Thanks in advance

 

[bimbla]

Look for BQ2031 in the TI site.

You will find all the info you want .

I hope that this helps.

bimbla.

 

[olemp]

i am not sure but:
give constant voltage and measure charge current. if it doesn't exceed the max. charge curent countinue to give constant voltage. if it exceeds decrease the voltage level until your charge current become less then max charge current........

 

[gidimiz]

Hi,
There is another simple way to charge ONLY lead acid battery. This methode is only if you have a voltage that is equale to your bettery.
What you need is a simple light bulb like the one that use in a flash light ( not the LED ) in series with your wire to the battery.
The idea is when the battery is almost full, then the current decresses and the resistance of the bulb increasses up to the point that you almost stop charging the battery.
All the securaty systems use that, very easy and very cheap.
Good luck.

 

[rad20]

Here's another source for SLA charging algorithm.

**broken link removed**