This project aims to develop and prototype Motivs Battery Charge Management System (BCMS) which was invented, simulated and patented completely with Motivs internal funds. Motivs BCMS balances series strings of battery cells within a large battery pack. It is a direct replacement for the resistive BCMSs used commercially today, but contains fewer components and is less expensive. It outperforms the more expensive, complex resistive battery balancing, allowing faster pack balancing with less wasted power. Motivs BCMS is based on capacitive energy transfer, but uses unique circuit layout and controls to avoid the typical pitfalls often associated with other capacitive designs, such as slow balance time and expensive hardware cost. The goals of this Phase 1 project will be: (1) design and prototype the Motiv BCMS hardware on a single 4.67kWh 16S2P battery module of 40 Ah cells, (2) develop and implement the control algorithm for the above module on an embedded microprocessor, (3) demonstrate balancing on this module that outperforms a standard baseline resistive BCMS from a variety of initial imbalanced conditions, and (4) quantify improvements versus the state of the art BCMS. After Phase 1, this project aims to continue development of the Motiv BCMS and demonstrate it on a full-scale automotive battery pack in Phase 2. Motiv will also engage commercialization partners ASIC (application-specific integrated circuit) manufacturers for building an ASIC to support the Motiv BCMS, making it almost a drop-in replacement for resistive BCMS ASICs, except with significantly improved performance and fewer necessary external components. Early simulations by Motiv show that its BCMS may increase pack available capacity from the 90% typical with a resistive BCMS1 to as much as 97% to 98%, thus adding thousands of dollars of value to each battery pack while decreasing cost, hardware complexity, waste heat, and pack balance time.
