The answer depends on the trim: the standard 2015 Malibu uses a single 12-volt battery, while the Malibu Eco variant with GM’s eAssist mild-hybrid system uses a second energy-storage battery, effectively giving two batteries in that model.
Battery configurations in the 2015 Malibu
GM offered both a conventional gasoline Malibu and a lightly hybridized version in 2015. Here is how the electrical systems differ by model.
Non-hybrid Malibu models
Gasoline-only Malibu models use a traditional 12-volt lead-acid battery to power the starter, electronics, and accessories. There is no separate hybrid energy-storage battery in these trims.
Malibu Eco and the eAssist hybrid
The Malibu Eco, equipped with GM’s eAssist mild-hybrid system, incorporates a second energy-storage battery for the hybrid function. In addition to the standard 12-volt battery, the car carries a smaller high-voltage/energy-storage pack to support start-stop, regenerative braking, and limited electric assist.
How to identify which configuration you have
Look for badges or model designations like “Eco” on the trunk or rear deck to indicate the hybrid variant. The Eco/eAssist setup also typically involves a visible difference in the trunk area where the hybrid battery pack is located, though exact placement can vary by production year and trim level. If in doubt, check the owner’s manual or have a dealer verify your specific VIN configuration.
Maintenance and practical implications
The 12-volt battery in all Malibu trims requires standard maintenance and eventual replacement like any other modern sedan. The Malibu Eco’s secondary battery pack is part of the hybrid system and is not user-serviceable in the same way; service typically involves the hybrid system's electronics and safety inspections by qualified technicians.
Summary
In the 2015 Chevy Malibu lineup, two-battery configurations exist only with the Malibu Eco hybrid version. The standard gasoline Malibu uses a single 12-volt battery, while the Eco adds a separate energy-storage battery to support the eAssist mild-hybrid system. If you’re unsure which version you have, identify the Eco badge or consult the vehicle’s documentation.