Need some advice for a lead acid battery charger

Hi all. I need to design and implement a lead acid battery charger in 2 months time. I started to read documents i found over the internet but it is getting more messy each time i looked at something. So i hope you can give me some advice for the road to success.
first of all i must charge 6 of the attached in order to energize two dc motors.View attachment akü.pdf
From my readings i come up with the idea that i must design an flyback smps with 14,4 v output for boost charge. Not sure if i have correct. And if so , than for trickle charge , do i need to design one more flyback?
And simulation issues ? spice or other software. Also I found out from the forum that there are plenty of online smps designer. Do they fit my aim?
And again from the forum some guy use pb137 for charging. Is it something like that pb137 vs smps for battery charger?
And lots of questions like that. So help me please time is ticking away

Thanks in advance.

Hi,

There are dedicated lead acid charger ICs. Use one fo them.
There are datasheets and application notes. They tell you all.

Klaus

you need a current limit as part of your charger, for a 20Ahr batt the current limit would be 2 amps (sealed batt), a circuit that takes the V up to 14.2 volts and then switches back to 13.50V once that target is reached or after a time out of 2-3 hours, then sit in float 13.50
This gives the best charge to sealed and wet Pb-acid batts...

Thanks for the answers.
I've began to search and already gave sample orders. But those ic need DC voltage in. So i think first should design a AC-DC power supply , following 6 charger circuits.

Hi,
You can try this circuit if ICs are easily available.
**broken link removed**

This circuit will work 230VAC when primary side designed for the same voltage

A lot depends on the application.

Charging a dead flat battery to as full a re charge as possible, as quickly as possible is one thing.

Keeping a large stand by battery fully charged and in good health for months or years that may only occasionally see a heavy discharge, and where a recharge can be quite slow is a very different thing.

The first can be a pretty simple dumb high power Brute Force charger.

The second needs a bit more sophistication in the control system, but may not need to be extremely powerful.