Yes, lithium batteries are suitable for use with outboard motors. We recommend the 12V 100Ah Cranking Dual Purpose Battery for use with starting outboard engines.Lithium batteries are often preferred over lead-acid batteries due to their superior energy efficiency, lightweight construction and long lifespan. However, it's important to ensure that the lithium battery you choose is compatible with your specific motor and that you follow the manufacturer's recommendations for charging and maintenance to ensure optimal performance and longevity.