A Modular Approach for Optimizing Battery Separators for High Charge-Acceptance and Other Desired Attributes
With the growing market for Enhanced Flooded Batteries (EFBs) the in the automotive arena, and increased opportunity-charging requirements in battery applications as diverse as Motive Power and Telecom, the need for enhanced charge-acceptance by lead–acid batteries has never been greater. Traditionally, battery companies have looked to increase charge-acceptance through product design (more lead) and additives (such as carbon to the negative active-material). There can be downsides to such approaches, e.g., significant cost increase with more lead and increased water consumption with the use of carbons. This presentation looks at the approach to maximizing charge-acceptance through separator design. Intuitively, one realizes that that charge-acceptance can be increased by minimizing the electrical resistance of the separator. The skill, however, is to maximize charge-acceptance whilst maintaining sometimes conflicting goals, such as excellent mechanical strength and durability. A modular approach to separator design will therefore be proposed. There are design parameters, material choices, additives and treatments that can be combined to optimize not only charge-acceptance, but also can be utilized to meet other battery design challenges such as water consumption and acid stratification. The presentation describes how customers can ‘mix and match’ the properties they want to see enhanced. Data for the properties of the separators as well as subsequent cell and battery testing will also be disclosed.
David Mihara has 34 years of experience in the battery industry. The first 23 years were in various engineering and R&D positions with Duracell and Rayovac, in both the USA and Europe. There followed over 11 years in the lead–acid field with Exide Technologies and NorthStar Battery Co. David is currently Vice President of Technology at Microporous LLC.