Direct Lamination Cooling of Motors for Electric Vehicles

60765 Current designs for electric motors use a housing that acts as both a structural support and as a method of cooling the stator and rotor. This approach to cooling is not as effective as possible because heat must flow from the rotor and stator through the housing to the cooling media. Because the housing must contain the coolant, it is also larger, heavier, and more expensive than necessary. This project will develop a motor that uses a direct lamination cooling (DLC) system, passing coolant directly through the stator and eliminating the need for bulky housing, thereby improving heat transfer. Motor size could be reduced by up to 30-40%, mass by up to 20-30%, and cost by up to 30%. Phase I demonstrated that reliable lamination-to-lamination seals and reliable stack-to-manifold seals can be achieved using the methods identified. The addition of the selected sealants adds only slightly to the thermal resistance and pressure drop compared with unsealed counterparts. Phase II will build electric motors and inductors using the DLC method, obtain comparative performance data on the effectiveness of the method, and then obtain operational use data on these components through long term testing in a representative environment. The long-term testing will ensure that real world aspects of motor and inductor operation (including vibration, temperature cycling , and the presence of electrical and magnetic fields) do not degrade the seals such that leaking occurs or that the thermal performance degrades. Commercial Applications and Other Benefits as described by the awardee: The DLC method should reduce the cost and increase the power density and specific power of electric motors and inductors/transformers thereby increasing the market penetration for these systems