How to externally power 12 mg996r servo motors

Other Hardware General Electronics
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Hi. I wanted to supply power to my 12 mg996r servos using nimh batteries which are 7.2V and has a max discharge rate of 30A. These are the batteries https://www.amazon.com/dp/B07VLKP6RJ?psc=1&ref=ppx_yo2ov_dt_b_product_details. I have multiple of these batteries and I was wondering how I can use them to power the motor.
Can I just split up the 7.2V output and ground to all my servos? I was thinking of using my breadboard but I remember checking the specs and they recommend 5V 3A which is way below what I have. So I wasn't sure if it'll cause my board to burn.
My initial plan was to use a motor driver PCA9685 and supply external power using this battery but I read that it has max 6v now and it only supplies 10A per board.
Anyways, any suggestions or help is much appreciated

Here's the schematic of the driver PCA9685:

71Iq+UI7wCL.AC_SL1500
71Iq+UI7wCL.AC_SL15001500×501 121 KB

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Servo power of a PCA9685 board has nothing to do with PCA9685 power.
Only PCA9685 ground and servo ground are shared.
Servo power (screw terminal) is only connected to the row of servo+ pinstrips, nothing else.
Check if the servos you use are 8.4volt tolerant (fully charged battery).
Another concern is the rather thin servo power/ground traces of a PCA9685 board.
You could beef them up with wires between the screw terminal and the pin strip rows.
PCA9685 power comes from the Arduino.
Leo..

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Keep in mind that the MG996R draws the start/stall current of 2.5 A, every time is starts moving.

Breadboards are completely out of the question for servo power.

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Interesting. The servos' max voltage is 7.2V so does this mean that I can't use these batteries for them? Or I suppose if I discharge them till it's safe it works? Also I did read that the 6V is the max for V+ but is that not the servo voltage? I assumed because it was right next to the power supply. Here's where I read about it pca9685 PWM 6 volts max?.
Sry bout the qs. Just wanted to make sure I don't burn anything.

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Ok thanks for pointing that out. I was thinking it'll fry.

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Can I supply power to them connecting the motors in parallel with a protoboard with beefy wire? I am mainly not sure of how to divide up the current between the properly.

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“ Can I supply power to them connecting the motors in parallel with a protoboard with beefy wire? I am mainly not sure of how to divide up the current between the properly.”

Yes

You can use a BOOST/BUCK converter to keep the voltage at 6V but these servos can be used down as low as 4.5V.

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Thank you so much! Lemme try the external part tomorrow.

For BOOST/BUCK converter I found the maximum output current seems to always be like 3A. Oh, can I just combine this with the wires to ensure that the servos get 3As all the time and won't suddenly get 20A or something?

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There are converters that can supply more current.

You can use several lower current converters to supply several servos.

Common GNDs between the supplies and Arduino.

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Thanks! I'll try this out. Just to summarize:
I should connect my power supply to a protoboard where have all my motors connected in parallel to the 7.2V and the ground of the power supply.
Here, I should have the converter in order to limit the current to 3A and keep the voltage in a safe range for the motors.
I suppose I shouldn't use resistors because it reduces the voltage. Anyways will report what happens

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