Development of Battery Technology in China

After determining the development direction of lithium batteries, scientists have begun to make efforts in the field of lithium batteries. As a result, lithium batteries with smaller size and higher density have emerged one after another.

However, the battery at this time is still called a lithium battery, not a lithium-ion battery.

Although lithium batteries are good, their disadvantage lies in the highly reactive nature of lithium, which makes them prone to explosions and spontaneous combustion, raising concerns about safety. At that time, out of ten lithium batteries, eight of them were prone to spontaneous combustion. Holding a lithium battery was like holding a burning bomb, which was extremely dangerous.

In the process of addressing the safety issues of lithium batteries, one scientist emerged as a prominent figure, and that was John Goodenough, often referred to as the “father of the lithium-ion battery.”

Goodenough successfully developed a method to break down metallic lithium into an ionic state, allowing lithium ions to shuttle between the positive and negative electrodes during the charging and discharging process. Due to the absence of metallic lithium and the presence of only lithium ions during the charge-discharge cycle, the safety of the battery was significantly improved. This type of battery is known as a lithium-ion battery.

Compared to traditional lithium batteries, the greatest advantage of lithium-ion batteries is indeed their improved safety, with a probability of spontaneous combustion occurring only in rare cases, estimated to be around one in ten thousand. However, due to the severe incidents of lithium battery fires in the past, there was reluctance among Western companies to adopt this invention when lithium-ion batteries were introduced.

The first country to adopt lithium-ion battery technology was indeed Japan. In the 1980s, Japanese electronic products dominated the international market, and there was a pressing need for advancements in battery technology. As one of Japan’s most powerful companies, Sony Corporation embraced John Goodenough’s lithium-ion battery technology.

Indeed, with the introduction of lithium-ion batteries, they received widespread acclaim, and Sony quickly emerged as a dominant player in the battery industry.

In 1997, John Goodenough further developed a new type of lithium-ion battery known as the lithium iron phosphate (LiFePO4) battery. This battery, once introduced, quickly gained attention for its stability and low cost, making it a prominent choice for large-scale applications. It gradually became one of the primary battery types used in new energy vehicles.

Goodenough’s contributions to lithium-ion battery research, including the development of the LiFePO4 battery, were recognized when he was awarded the Nobel Prize in Chemistry in 2019.

Although lithium-ion batteries currently dominate the consumer electronics market, lithium-ion technology is not the pinnacle of battery development. There is still potential for further improvement in safety and energy density.

Chinese battery companies have made significant strides in exploring these areas.

To increase the driving range of electric vehicles, there are currently two main approaches. The first method is simply to increase the battery capacity. The larger the battery, the longer the driving range. However, this approach leads to increased weight, higher costs, and safety concerns. In response to these challenges, BYD (Build Your Dreams) developed blade batteries.

Blade batteries, developed by BYD, utilize structural innovation by elongating the battery cells to increase their length. The battery casing itself provides some structural support for the battery pack, thereby enhancing energy density while ensuring safety.

The second approach, as seen in Tesla’s technological path, focuses on software optimization. By utilizing intelligent electronic control systems, Tesla optimizes the allocation and usage of electrical power, aiming to minimize energy consumption while maximizing power output. If we can say that BYD adopts a “brute force” technology route, then Tesla follows a “smart and efficient” technology route.

However, regardless of which technological path is taken, without substantial breakthroughs in battery technology, these approaches are merely temporary solutions. To fundamentally address the issue, battery technology needs to be revolutionized.

In this regard, Chinese companies are indeed at the forefront of exploration.

Sodium-ion batteries are considered an important direction for future development, and China’s power battery company, CATL (Contemporary Amperex Technology Co. Limited), is currently leading the development of sodium-ion batteries.

CATL has introduced its first generation of sodium-ion batteries. While their energy density still lags behind that of lithium iron phosphate and ternary lithium batteries, sodium-ion batteries exhibit better performance at low temperatures. They can retain over 90% of their range capability even in environments as cold as -20 degrees Celsius. Additionally, sodium-ion batteries offer fast charging speeds, allowing for an 80% charge in just 15 minutes at room temperature. This addresses the concerns regarding slow charging of electric vehicles compared to the convenience of refueling.

While using sodium as the material solves the issue of the positive electrode in the battery, the question remains: What about the negative electrode?

Silicon-based materials are currently the highest-capacity negative electrode materials for batteries. In theory, they can handle current densities up to 12 times higher than graphite. China has also made significant advancements in this area, with a project called “Qinghai Lake Battery” that has been applied to smartphone projects. This technology enables batteries to be made with a thickness of less than one centimeter. Many foldable screen smartphones use silicon-based batteries.

Overall, China’s battery technology is currently at the forefront globally. This solidifies a strong foundation for China’s future development in the field of new energy.