lifepo4 charger

Hi;

İ have 12,8V 18A batteries. İ want to charge them with 10 parallel. i will buy 14.5V -50A charger but i need current limiter at 5A for each one battery. How can i design it. Do you have suggest for circuit or method

Hi,

In my eyes this makes no sense.

A 50A charger will - at least temporarily - run in constant current mode. Indeed it is a current limiter.
During this time when you "limit" the cell current to 5A ... you already generate a current limiter..in total 10 x 5A = 50A.
So why do you need a 50A current limited charger at all?
And in case it "switches" the cell OFF the 50A will be spread to the remaining cells. What will happen?
In either case it means that the 50A charger will see an increased cell voltage ... so it can't measure true cell voltage and thus can't work properly.
I'd say it's no good idea.

Either you do the parallel charging, maybe with reduced total current, and accept current imbalance.
Or you do serial charging with a balancing circuit.

Klaus

hello
what is the type of your batteries (Ni-Cd) or (lead-acid) or( lithium-ion battery)?. to charge any type of them
without you cause a damage( overcharging )to them .any type should be charged by rate voltage ( float-charge voltage ) and you should not exceed this rate . There are three common methods of charging a battery; constant voltage, constant current and a combination of constant voltage/constant current.

kamal

Hi,

Apart from Li-ion string charger/monitor IC datasheets, LED open string and short string protection circuits might give you some interesting ideas.

... Or e.g. op amp clamp as variable reference with 5V ( = 5A) limit for OA + mosfet CCS?

Lifepo4 battery i use. İn that case how should a method i follow. Which charger i have to buy

mosfet123 said:

Lifepo4 battery i use. İn that case how should a method i follow. Which charger i have to buy

Click to expand...

You say you have 12.8V batteries; they must be series (or both series and parallel) connected. Such connections are most commonly done via a BMS (battery management system) module. This module most commonly takes care of the charging and discharging rates. This is mpt clear from your description. Please provide more details.

You mention that your battery is 18A rated; usually they are specified in AH capacity and the max disch curr is determined by the BMS. The suggested charging curr is usually spec in terms of the AH capacity.

In short, incomplete information provided.

you can have your 14.5V charger - just put a resistor in series with each battery - this will ensure even charge distribution - until they are fully charged ...