Can poor soldering of ESC wires lead to low voltage draw from a Lipo battery?

Question

Question:

Would improper soldering of the power wires of my electronic speed controller limit the amount of voltage that my ESC draws from the Lipo battery?

My situation:

I have to solder an XT60 male connector onto the power terminals of my ESC. As you can see in the highlighted part of the picture below, my ESC has no connectors on it. My ESC is the QWinOut 2-4S 30A ESC which can be found: https://qwinout.com/products/qwinout-2-4s-30a-rc-brushless-esc-simonk-firmware-electric-speed-controller-with-5v-3a-bec-for-2-to-4s-lipo-battery-diy-multicopter-quadcopter

This male connector will be joined with a female connector that is attached to my Lipo battery which is a 1300mAh 2S 20C battery.

I need this connector so that I can power my motor which is a 1000KV motor. This motor came packaged with the ESC and is designed for that ESC. It can be found on: https://www.amazon.com.au/QWinOut-Brushless-Outrunner-Multi-Copter-Quadcopter/dp/B07CVDHQKS

I had a great deal of difficulty soldering the terminals of my ESC onto the male connectors. My fear is that improper soldering will mean that when I connect my ESC to the battery, the ESC will not draw its rated voltage. As a result this would damage my LiPo battery?

For extra information:

My code and wiring will be identical to the one in this video. https://www.youtube.com/watch?v=uOQk8SJso6Q

Answer 1

Your concerns are in the right place, but the reasoning is incorrect.

First things first:

You don't draw voltage from a battery

Current flows as a result of differential voltage. The ESC doesn't tell the battery how much voltage to put out, or even how much current. Current flows based on the load of the motor.

Having a bad connection will cause the voltage at the ESC to be lower than the battery voltage, but only because the bad connection is acting as a resistor. It will get very hot, wasting energy that could be sent to the motor as heat. Sometimes this can cause the solder to melt at the connection, and come loose. This is then dangerous as the loose cable can cause a short circuit.

The battery won't be damaged

The battery will not be damaged by a poor connection (unless you cause a short circuit). In fact, the current will be lower and your battery will be happy to chug along at the lower current. This doesn't mean you don't have to keep an eye on the battery voltage - if it is low, then you can damage the battery by over-discharging. Always keep the battery within 20-80% state of charge (you can go up to 100% before using it, but don't store it like that).

Proper solder joints are critical

Practice soldering, get a practice kit, or hopefully you have enough spare xt60s to practice on. Use flux and a flux core solder, keep the tip wetted with solder all the time, and make sure you're getting enough heat that the solder flows nicely, without overheating the connector. Add solder at the joint, not on the iron. a 40W iron is a little small for xt60s, so hopefully you have a 60W or higher.

Post pictures of your solder joints on Reddit (or another forum-like site), and ask what you can improve. You will always be able to improve something.

Your setup seems weird

a 1000kV motor (I'm guessing a suppo 2212 based on the ESC that it came pre-packaged with) on 2S lipo would need to spin a large prop to be worthwhile. This is a discussion for another question entirely, but the aircraft you intend to put this on might be underpowered.