Smart Battery Backup System

In an example, a smart battery backup system is disclosed. The system is configured to be installed on or within a vehicle and connected to a main battery of the vehicle. The system includes a housing, a lithium-ion battery disposed at least partially within the housing, and a controller disposed at least partially within the housing and including a set of momentary switches. The controller is configured to jump start the main battery using the lithium-ion battery. The controller is also configured to maintain the lithium-ion battery such that, based on a charge state of the lithium-ion battery and a charge state of the main battery, the lithium-ion battery is charged using the main battery.