Battery Switching system

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1

Hi there, I am sorry if this is a repeat of a post or in the wrong forum, though I couldn't find anything that discussed what I am looking for. I am also someone with little experience with circuit design and Arduino.

Do people know a circuit design that switches between multiple batteries using an Arduino? The Arduino monitors the battery, till it runs out and then switches to the next battery, most of what I see is people saying why bother and just put them in parallel.

This doesn't work for me as I have 12 x 48V batteries as this would spike the amps to over 100A which none of my electronics can handle (I am constrained to these batteries so I am not able to buy anything else). I will be stepping down the voltage already for the Ardiuno and my electronics but not sure anything exists for 576V if the batteries are in series, not to mention the risk of high voltages and amount of power wasted in doing so.

These batteries will also be constantly charged by multiple systems. However the output power will be higher than input power.

What I see some people to use MOSFETs from my understanding MOSFETs are two diodes and I am not sure how I would implement that.

Also could I use a capacitor to keep the Arduino and other system running while switching batteries?

2

The batteries cannot cause cause such a "spike"
It is the load that determines how many Amps are used.

3

Off-the-shelf, I don't think so . You would need a custom PCB.

4

It’s smart to separate the supply to the Arduino from the supply to the user.

At the current needed for the Arduino simple diodes to feed the DC-DC converter will do.

Feed the battery voltages via dividers to the analog inputs to decide which battery to use.

Multiple Batteries
Multiple Batteries1648×1168 3.01 KB

You mentioned a transistor to be two diodes, for old-fashioned transistors that is more or less true, not so for MOSFETs.

I’ve drawn relays for the motor current, if the switching times of the relays are known you can do break-before-make while the motor keeps running without a noticeable hitch.

5

Picture 2 car batteries, one at 10V (dead) and one at 14V (helper car) and connect these with jumper cables of a few milliohms. Do the math.