The fact that it's a Li-ion battery gives the controller module at least two required functions. First in charge mode, cutoff charging current when battery reaches 4.2vdc as over charging can damage the battery. Second is a load disconnect to prevent the battey from discharging below around 3.5vdc or so as over discharging will also damage the battery. Other then that you should be free to wire any reasonable load to the modules output.
Lefty