Simple electrode assembly engineering:Toward a multifunctional lead-acid battery

Electrochemical energy storage is a promising technology for the integration of renewable energy.Lead-acid battery is perhaps among the most successful commercialized systems ever since thanks to its excellent cost-effectiveness and safety records.Despite of 165 years of development,the low energy density as well as the coupled power and energy density scaling restrain its wider application in real life.To address this challenge,we optimized the configuration of conventional Pb-acid battery to integrate two gas diffusion electrodes.The novel device can work as a Pb-air battery using ambient air,showing a peak power density of 183 mW cm^(−2),which was comparable with other state-of-the-art metal-O_(2)batteries.It can also behave as a fuel cell,simultaneously converting H_(2)and air into electricity with a peak power density of 75 mW cm^(−2).Importantly,this device showed little performance degradation after 35 h of the longevity test.Our work shows the exciting potential of lead battery technology and demonstrates the importance of battery architecture optimization toward improved energy storage capacity.

Simple Rational Model for Discharge of Batteries with Aqueous Electrolytes, Based on Nernst Equation

A simple rational model is proposed for discharge of batteries with aqueous electrolytes, based on Nernst equation. Details of electrode kinetics are not taken into account. Only a few overall parameters of the battery are considered. A simple algorithm, with variable time step-length Δt, is presented, for proposed model. The model is first applied to Daniel cell, in order to clarify concepts and principles of battery operation. It is found that initial pinching, in time-history curve of voltage E-t, is due to initial under-concentration of product ion. Then, model is applied to a lead-acid battery. In absence of an ion product, and in order to construct nominator of Nernst ratio, such an ion, with coefficient tending to zero, is assumed, thus yielding unity in nominator. Time-history curves of voltage, for various values of internal resistance, are compared with corresponding published experimental curves. Temperature effect on voltage-time curve is examined. Proposed model can be extended to other types of batteries, which can be considered as having aqueous electrolytes, too.