Technical challenges in low-temperature environments

The core advantage of reserve power supply lies in the separation of electrolyte and battery cells before activation, which can achieve storage for up to 20 years without self discharge. But when the temperature drops to -50 ° C, the electrochemical process of the lead-acid system significantly slows down, and the activation time is difficult to shorten to less than 100 milliseconds. Although an activation time of 29-45 milliseconds can be achieved at -32 ° C by optimizing the electrolyte flow resistance, further breakthroughs at lower temperatures are difficult. This has led many applications to shift towards higher cost lithium thionyl chloride systems.

Research breakthrough: Microstructure reshaping performance

The research team utilized Zeyou Technology's ZEM desktop scanning electron microscope to conduct in-depth microscopic analysis of electrode materials and explored two innovative paths.

The attempt and challenge team first attempted to replace traditional lead anodes with zinc. Although zinc significantly increases the discharge voltage at low temperatures, it leads to unstable discharge characteristics and affects the reliability of the power supply. The above figure clearly shows the different material systems inPerformance differences at temperature.

The key role of nanopore structure research has shifted towards optimizing the nanopore structure of lead dioxide cathode materials. By precisely controlling the electrode preparation conditions, the team successfully regulated the microstructure of PbO ₂ coating.

Scanning electron microscopy images of PbO ₂ coating surfaces obtained from different preparation schemes: 1 (a), 2 (b), and 3 (c, d, e)

The scanning electron microscope images clearly revealed the surface morphology differences of PbO ₂ coatings under different preparation schemes, providing a visual basis for optimizing the process.

Innovative design: Balanced performance of double-layer structure

The research team has developed a unique double-layer structure design that combines a dense PbO ₂ inner layer with a porous outer layer, ensuring high discharge capacity and achieving rapid activation.

Figure Two layer structure model of lead dioxide (PbO ₂) cathode

This design performed well in experiments, and the power supply based on the Pb-HClO ₄ - PbO ₂ system was able to maintain stable discharge at -50 ° C.

Practical application verification

The team manufactured a micro battery test batch with a volume of only 0.02 milliliters. The test results show that the optimized reserve power supply achieved an activation time of less than 30 milliseconds in a -50 ° C environment, and the discharge voltage was stable, with performance far exceeding expectations. This breakthrough has made lead-acid systems a viable choice for low-temperature reserve power sources, bringing more cost-effective solutions to related fields.

Technological prospects and challenges

Despite significant achievements, the research team points out that issues such as long-term stability still need to be addressed. The preliminary results of the accelerated life test currently underway indicate that the optimized PbO ₂ coating can still maintain good performance after storage. The ZEM series desktop scanning electron microscope from Zeyou Technology played a key role in this study, with its high imaging speed and diverse signal detection capabilities providing strong support for the microstructure analysis of electrode materials. This research not only promotes the development of lead-acid battery technology, but also opens up new avenues for power solutions in the environment. With further optimization, this technology is expected to achieve breakthroughs in more key areas.