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Series and Parallel on Batteries
Safety and Temperatures: It's important to set your soldering iron to a high temperature, like 351 degrees Celsius, and to avoid breathing in the fumes [00:01].
Soldering Techniques: To ensure good coverage and buildup, apply the solder directly onto the tip of the iron [00:10]. Work quickly so the solder doesn't dry out and ruin the tip of your iron [00:45].
Maintaining the Tip: Keeping the iron's tip "wet" with solder prevents it from crusting up and becoming difficult to work with [00:50]. A neglected tip may eventually need replacement [01:02].
When Finished: Remember to turn off the soldering iron when you are done [01:02].
Series Connection: This involves connecting the positive terminal of one battery to the negative terminal of the next. In a series setup, the voltages add together, but the capacity (Ah) remains the same as a single battery. For example, two 1.5V batteries in series provide 3V.
Parallel Connection: This involves connecting all positive terminals together and all negative terminals together. In this setup, the voltage stays the same, but the capacity adds together, allowing the device to run for a longer period.