Li-ion Batteries and the Electrification of the Fleet

Lithium-ion (Li-ion) batteries have begun to proliferate across the U.S. Navy fleet, commercial shipping, and in many other naval contexts. Naval engineers must account for Li-ion batteries when designing new vessels to ensure safety and adequate integration of the batteries into ship electrical systems. This article examines current Li-ion battery usage and predicted battery requirements for the U.S. Navy's operating force in 2035 and 2045 from a mission engineering perspective and surveys battery chemistry, energy density, charge/discharge rate, safety concerns, etc. Projections of future battery requirements for the operating force in 2035 and 2045 are developed which clearly show that several classes of vessels will have significant growth in Li-ion batteries aboard the future fleet. The role of Li-ion batteries, however, will likely be limited to running specific subsystems or equipment and will not replace ship generators. This will remain true until the energy density of battery technology even begins to approach that of petrochemicals, which is many years away if possible. With recent high-profile Li-ion battery fires aboard civilian vessels, this research makes clear that Li-ion batteries will become more prevalent aboard ships over the next 20+ years and that naval engineers must begin accounting for Li-ion batteries now.