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Charge And Load Questions Searching For An Auto-Switching Circuit

Hello everyone,

Does anyone know of any shield/ready-made circuit that would allow to automatically switch from charger's power source to battery and vice versa ? That would allow my batteries to fully charge while docked. I think I don't even know the proper keywords to search online for such a circuit.



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Depending on the load and the charger you may be able to do that without a changeover switch.
Good question. I was actually wanting to look into a switch that would change over to batteries when the power was switched off. I'll be watching this thread for suggestions.
I use these , they have larger versions for higher current but this is a circuit that is a battery charger and also a switching supply. It can charge anytime and it power is cut it swaps to battery power without shutting the robot down. This was my solution for autonomous auto charging without powering off. You could parallel for higher current capacity and its cheaper to buy then pulling a soldering iron out and making one yourself;)
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10 amp version

20 amp version
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10 amp version is 120 watts of continuous power to your robot from your batteries , that is plenty to drive 90 percent of projects out there but I wanted to show options for big guys too. this could be beneficial because you can remove the PCB from the case and its very compact and is already a charging circuit. All you need it a DC plug and plug your robot in and it charges without shutting down. Also beneficial is if you want to finagle a charge dock your your robot.
I see that all models seem to work with 12v batteries. My robot works on 8V lipo, do you think it would still do the job ?
It would run but charging circuit would not work properly and overcharge a battery. My best recommendation would be swap to a 3s lipo 11.1 volts which I believe is 12.6 charged. and if you need voltage dropped for a certain reason then you could use a voltage regulator. The great news is using a battery with a baseline voltage that is higher is you will not ever have a brown out or voltage sag.