Hi

I need a charger that can sequentially charge 10x LiPO4 12V batteries. The batteries are connected to separate loads and each takes a 20A max charge current.
The charger needs to be smart enough to send/receive email or txt commands. I can't find a charger off the shelf to do this so I will have to design one.

I have found the LTC4000 family which looks like it could do the job.
I have also found some designs with embedded PIC type circuits but these seem to be > 10 years old. Perhaps these preceded the purpose made devices.

Does anyone have recent experience designing high powered chargers?
What is the favoured architecture?

 

Hi

I need a charger that can sequentially charge 10x LiPO4 12V batteries. The batteries are connected to separate loads and each takes a 20A max charge current.
The charger needs to be smart enough to send/receive email or txt commands. I can't find a charger off the shelf to do this so I will have to design one.

I have found the LTC4000 family which looks like it could do the job.
I have also found some designs with embedded PIC type circuits but these seem to be > 10 years old. Perhaps these preceded the purpose made devices.

Does anyone have recent experience designing high powered chargers?
What is the favoured architecture?

That is a very high charging current for a lithium technology battery, and, actually, for any kind of battery. Therefore, guessing that you have a whole lot of money invested in those batteries, I suggest contacting the battery manufacturer and ask for their recommendations for both the exact charging process and also a recommended charging system. They should be able to provide that information for free.

 

Hi
The tech specs are based on the battery makers recommendations. They are big batteries and worth lots of $$$.

Regardless of current, the charging process is the same so the current isn't the key design factor for the architecture. At present, I think the LTC range is the way to go. The major disadvantage is that they are programmed with component values. That makes them difficult to modify after deployment.

 

The major disadvantage is that they are programmed with component values. That makes them difficult to modify after deployment.

You could use DIP (or other type of) switches to select the desired component values

 

You could use DIP (or other type of) switches to select the desired component values

Hi
I would have concerns about the long term stability of contact resistance and their affect on tolerances. Maybe a better option would be to use a voltage controlled switch for high tolerance variables (eg. charge current) under the control of a PIC or similar. I will need one of those anyway to allow remote control of the charger.

One of the nice things about software controlled systems. They can be a lot more flexible but that flexibility comes at a cost. Although there are software controlled RC model type chargers (I own one), they are designed to charge many battery types and capacities. I only need to charge one battery type and maybe 2 sizes.

 

Maybe a better option would be to use a voltage controlled switch for high tolerance variables (eg. charge current)

Just make sure the switch ON resistance is much less than the resistor tolerance (i.e. <<1% of the resistor value for 1% resistors).