What is meant by deep discharge of a battery?
Deep Discharge means the state of the battery lesser than the desired safer level. This reduces the battery life to a dangerous extent. Moreover, one of the biggest killers of batteries is sitting stored in a partly discharged state for a few months. A “float” charge should be maintained on the batteries even if they are not used (or, especially if they are not used). Also, batteries self-discharge faster at higher temperatures.
