Soldering a T connector is as simple as a banana connector. The only difference is that instead of one you will have to solder two pins; one for the positive and one for the negative wire. This kind of connector is called T because it consists of two pins in the shape of the Greek letter T. It is quite useful for these kinds of connections, since it can safely prevent reversing the connector, which will damage the battery and electrical components.

In the following image, the connector is half connected (male to female). At the left and the right side, we will solder our wires:

First of all, we need to strip two wires (if they are not already stripped) and find out which one is the positive (+) and the negative (-). Note that almost all batteries already have a T connector and you can easily find out the positive and the negative pin. Be careful not to solder it in the wrong order as this will destroy your battery:

Hold your connector with your helping hand and lace...