High Energy Density Lead Acid Battery with Titanium-Based Negative Grids Employing Expanded Mesh Sandwich Structure

Abstract

Addressing the low energy density issue caused by the heavy grid mass and poor active material utilization, a titanium-based, sandwich-structured expanded mesh grid (Ti/Cu/Pb) for lead-acid battery negtive plate is introduced. Titanium is chose for its advantageous properties such as low density, high mechanical strength, and good electrical conductivity, which reduces the electrode mass and enhances battery energy density. However, titanium's use in battery negtive grids is limited due to its passivation in sulfuric acid and poor adhesion to the active material. To overcome these drawbacks, a copper layer is added to prevent passivation, and a lead layer is applied to improve the adhesion between the titanium matrix and the active material. This innovative Ti/Cu/Pb negtive grid reduces plate mass and increases current density, boosting active material utilization. Plate with Ti/Cu/Pb negtive grid achieves an energy density of up to 163.5 Wh/kg, a 26% increase over conventional lead-alloy plate. With Ti/Cu/Pb negtive grid, battery cycle life extends to 339 cycles under a 0.5C 100% depth of discharge, marking a significant advance over existing lightweight negtive grid batteries. This research not only demonstrates a significant step in lead-acid battery enhancement but also proposes a methodological approach for future high-energy-density battery design.

Keywords: Lead acid battery, negative electrode grid, titanium matrix, cycle life, energy density