The original Tesla Roadster used a battery pack with a capacity of about 53 kilowatt-hours.
The pack was built from thousands of lithium-ion cylindrical cells, a format that helped Tesla achieve substantial energy storage in a relatively compact sports-car package. The Roadster’s battery system was one of the vehicle’s most important innovations because it combined high performance with usable driving range.
Tesla later offered battery improvements and replacement programs, so published capacity figures can vary depending on whether a source is discussing the original pack, an upgraded pack, or usable rather than nominal energy.
The 53-kWh figure refers to the original production Roadster specification. It should not be confused with the larger packs used in later Model S, Model X, or Model 3 versions.