PEM fuel cell architecture (Proton Exchange Membrane) inspires battery developers to innovative integration of lead-carbon batteries with an electrode-electrolyte assembly that promises improved electrochemical performance and lower discharge variation.
A study published in Journal of Energy Storage describes research made by a group of scientists at the São Paulo University in Brazil. Lead batteries are still considered a good option for many applications thanks to a good cost-performance ratio. The lead-carbon composite battery is an attempt to replace the heavy lead grids with lighter alternatives.
This battery technology is commonly referred to as carbon‑lead-acid battery (CLAB). The researchers say that it currently is the only viable, mass-produced technology available for start-stop systems and basic micro-hybrid vehicles. It is expected that CLAB technology will play a significant role in grid energy storage applications in the future.
The lead‑carbon material is synthesised with a 40 % mass ratio using the Flash Joule Heating Method. The use of nano-Pb/C composite materials demonstrates higher conductivity and lower ion transfer resistance. Lead‑carbon materials for CLAB exhibit electrochemical characteristics like metallic lead. Carbon does not participate in the electrochemical process but enhances the corrosion and stability of lead, inhibiting the formation of species (e.g. lead sulfate) that deteriorate the discharge characteristics of the positive electrode.
The researchers focused on the technology of PEM fuel cells. In these devices, the active metal is deposited in a layer of a few micrometers, laid upon a backbone of carbon cloth, where lead nanoparticles can be deposited, increasing stability and reducing weight. The thin layers of active material from the anodic and cathodic electrons are then separated by a proton-exchange membrane, which facilitates the transport of H+, avoiding gas evolution. This electrode structure with a polymeric electrolyte enables the production of a flexible device, giving engineers the possibility to construct or accommodate it in various types of spaces.
