Silicon composite anode-based lithium ion battery actuators have strong potential for large actuation strain, complex shape change, and large compliance tunability. This allows for actuators with potential to do work with no energy expenditure beyond parasitic losses to internal resistance. This paper studies a bimorph actuator comprised of two Li\[NiMnCo\]O~2~ cathodes coated on aluminum foil, a silicon-based composite anode double-side coated on copper foil, and a plastic separator placed between the double-side coated anode and two cathodes.

            The bimorph design allows for a nearly 360ᵒ range of motion and doubles the capacity of the battery.  An Euler-Bernoulli  model is developed to predict free deflection, blocked, force, and actuation force for given prescribed displacements for a range of geometric configurations and states of charge of the bimorph. By modeling the charging of both active sides of the bimorph simultaneously, it is possible to achieve zero bending while still accommodating for the volumetric expansion of the silicon.  The bimorph is able to achieve actuation force in one given direction by charging each anode coating separately or maintaining a charge difference between the two coatings. The former method allows for the accommodated volumetric expansion of silicon while maintaining zero bending as in a conventional battery setup.  The latter method allows for increased battery capacity and range of motion for a novel electrochemically-based actuation mechanism.


Analytical Modeling of a Segmented Bimorph Lithium Ion Battery Actuator

Division / Sponsors: 
Aerospace Division

Paper Proceedings: https://asmedigitalcollection.asme.org/SMASIS/SMASIS2020/volume/84027

SMASIS2020 - Virtual Conference

Supporting the need among researchers worldwide for additional online and multimedia content, ASME now offers the ASME Conference Video Collection. This platform will collect and provide long-term access to conference presentation videos, encompassing all technology areas within ASME's technical conference and events program. About 30,000-40,000 engineers across all mechanical engineering and related disciplines participate in ASME conferences each year. This includes authors of approximately 6,000 to 8,000 technical papers published by ASME, the majority of whom also submit video presentations for our virtual conferences. The video collection will be available as an add-on to existing product packages or as a separate subscription.