Why can’t lithium batteries replace lead-acid batteries

When Gaston Plant invented the lead-acid battery more than 160 years ago, he might not have imagined that his invention promoted the development of a multi-billion dollar industry. Currently, lead-acid batteries account for 70% of the global energy storage market, with a scale of approximately US$80 billion. Lithium battery is an emerging industry, but also has a relatively large development potential. But at present, it is difficult for lithium batteries to replace lead-acid batteries. The main reason is that lead-acid batteries have their own unique advantages. The advantages of lead-acid batteries are mainly manifested in the following 4 points.

1. Wide application

It has been widely used in uninterruptible power supplies, power grids, and automobiles (fuel vehicles, hybrid vehicles and new energy vehicles) and other fields. In the future, the performance goals of lead-acid batteries mainly include improving material utilization through more effective use of active materials, achieving faster charging speeds, further extending cycle life and mileage life, and reducing overall cycle costs.

2. Fully developed technique

In each charge and discharge cycle, the continuous dissolution and redeposition of battery active materials will cause continuous changes in the morphology and microstructure of the positive and negative electrodes. Generally these structural changes will corrode the electrode grid made of pure lead/lead-calcium/lead-antimony alloy and affect the cycle life and material utilization of the battery.

Since this morphological evolution is indispensable to the operation of lead-acid batteries, the discovery of its control mechanism at the atomic scale is expected to open up a new developments in the fields of material design, surface electrochemistry, high-precision synthesis, and dynamic management of energy materials. Scientific direction. Maintaining the entire electrode surface area can ensure an effective charging and discharging process, it is expected to have a direct impact on battery life.

Considering the complex interactions between the electrochemical and chemical processes of lead-acid batteries, these processes occur on multiple scales, with particles ranging from 10 nanometres to 10 meters. In lead-acid batteries, the active materials lead and lead dioxide are encapsulated into self-structured porous electrodes through traditional processes. During discharging, Pb2 ions react rapidly with sulfuric acid in the electrolyte to form insoluble PbSO4 crystals.

The complex interaction of electrochemical and chemical processes in lead-acid batteries at multiple scales. Exploring the electrode process at the atomic level will provide an effective way to improve the efficiency, life and capacity of lead-acid batteries.

3. Lower cost

The future of lead-acid batteries may be grid storage, and its future market is estimated to be around several trillion dollars. After reducing production and material costs and solving technical obstacles, lead-acid batteries are expected to become an attractive solution for grid energy storage. At present, lead-acid batteries have basic economic potential and can provide energy storage of US$20/kWh.

Although there is competition between lead-acid batteries and lithium batteries based on the energy density index, lithium-ion batteries are generally used for portable applications considering size, and lead-acid batteries are more suitable for energy storage applications considering cost. In fact, lithium batteries divide the nickel-metal hydride and nickel-cadmium battery markets even more.

4. Fully environmental measurement

In general, the focus of lead-acid batteries is mainly on the harm to human health and environmental pollution. In fact, after years of development and strict laws and regulations, the recovery rate of lead-acid batteries has reached 99%. On the contrary, lithium batteries still have many human safety and health issues, including: 1) the potential carcinogenicity of nickel and cobalt oxides in cathode materials; 2) thermal runaway events (battery fires and explosions) and the production of highly toxic organic fluorophosphate Neurotoxin; 3) Potential environmental pollution caused by toxic organic fluorine by-products in electrolytes and additives.

The lead-acid battery recycling rate of 99% and strict lead emission environmental protection regulations have greatly reduced the environmental pollution caused by lead. However, due to the lack of recycling solutions for lithium battery technology in the short term, the number of batteries reaching their service life has increased, and the potential harm of lithium batteries to the environment has increased.

Although in the past 30 years, lead-acid batteries have made great progress and applications, but researchers still need to continue to work hard for the technological development of lead-acid batteries.