The Breakthrough of BYD: Replacing Lead-Acid Starter Batteries with Lithium Iron Phosphate Batteries

In 1927, Bosch invented the lead-acid battery for automobiles. Today, lead-acid batteries have been applied in the automotive industry for almost a century.

Some people see tradition as inevitable and follow it without question, while others ask “why” and seek to make changes.

BYD belongs to the latter group. Recently, BYD announced that it has fully switched from lead-acid batteries to lithium iron phosphate batteries for its plug-in hybrid vehicle starter batteries, breaking a century of tradition.

This kind of subversion of automobile tradition is not new to BYD. Since entering the automotive field, BYD has been using its own technologies to change the appearance of automobiles, including the world’s first mass-produced dual-mode electric car, global promotion and application of lithium iron phosphate electric vehicles, the world’s first plug-in hybrid engine with a thermal efficiency of 43.04%, self-developed IGBT 4.0 with an electronic control efficiency of 98.5%, the first mass-produced “eight-in-one” electric powertrain, and a blade battery that can pass needle puncture tests.

Compared to other components, the starter battery replaced by BYD is not a major part. However, this measure indicates that BYD’s advocacy and promotion of green revolution is comprehensive. No matter how big or small, as long as it contributes to carbon neutrality and sustainable development, BYD will wield its sword of green technology to quickly cut off all sources of emissions and pollution.

Lead-Free New Energy Vehicles

As early as 2015, BYD began using lithium iron phosphate instead of lead-acid batteries as automotive starter batteries.

The earliest models to be replaced included the pure electric BYD e5 and the plug-in hybrid Qin DM and Tang DM.

The benefits of replacing lead-acid batteries with lithium iron phosphate batteries are obvious.

Firstly, many car owners may have encountered the situation where the small battery is dead. Inexperienced car owners may call for assistance, while experienced ones may ask to borrow a friend’s car battery to charge it.

The small battery mentioned here, the starter battery, is generally a lead-acid battery. The situation of being out of power is caused not only by excessive use of in-car electrical appliances, but also by self-discharge. Compared with lead-acid batteries, the self-discharge of lithium iron phosphate batteries is low. For example, in a month, the self-discharge of lithium iron phosphate batteries is less than 1%, while that of lead-acid batteries may reach 15-30%.

Secondly, the lifespan of lead-acid batteries is short, generally around 500 cycles, while that of lithium iron phosphate batteries is at least 3000 or more. This means that the entire vehicle’s battery needs to be replaced every 2-3 years. But with lithium iron phosphate batteries, the battery can last the entire lifespan of the vehicle without needing to be replaced.Compared with lead-acid batteries, lithium iron phosphate batteries have much lower energy density. Generally, the weight of lead-acid batteries is over 10 kg, whereas the weight of BYD’s lithium iron phosphate starting battery is around 2-4.8 kg. For car companies pursuing ultimate weight reduction, this is a significant benefit. Moreover, lithium iron phosphate starting batteries are much smaller in size, which is convenient for the layout of the whole vehicle. Some models of BYD, for example, place the starting battery under the front passenger seat.

The advantages are obvious, so why do most companies not make the switch?

First of all, switching from lead-acid to lithium-ion requires the transformation of the power supply and electrical systems. For many car companies, they prefer to choose mature solutions rather than entering into the unfamiliar field of power supply. Secondly, the cost of lithium-ion batteries is higher. Finally, many people are accustomed to thinking that lead-acid batteries, despite the problems mentioned above, can discharge at high rates, including under low-temperature conditions.

However, these problems do not exist for BYD. Firstly, for “technology maniacs” like BYD, many of the vehicle power sources and electrical devices are self-developed and self-supplied, so a comprehensive transformation is not difficult. Secondly, BYD mass-produces lithium iron phosphate batteries. In 2020, BYD’s installed capacity of power batteries alone was 3.88 GWh. In terms of marginal benefits, the advantages of lithium iron phosphate batteries are significant. Thirdly, BYD has been researching lithium iron phosphate batteries since 2002. Nearly 20 years of experience has made BYD a well-deserved expert in lithium iron phosphate. Its products have surpassed lead-acid batteries in terms of high-power discharge and low-temperature performance.

Furthermore, BYD has full control of electric vehicle power sources and battery technologies. In pure electric and plug-in hybrid models, it can achieve good synergy between starting batteries and power batteries.

For example, BYD has incorporated starting battery management into the overall BMS supervision. Once the starting battery’s power is low, it can be charged by the power battery. Users do not have to worry about a lack of power in the starting battery. Also, there is no need to leave much redundancy in the starting battery’s power, which can be smaller than that of a lead-acid battery, further saving space and weight.

As such, BYD has become the leader in unleaded starting batteries, and this is only natural.

Why is it BYD?

Replacing the century-old lead-acid starting battery with lithium iron phosphate is just one example of how BYD revolutionizes the automotive industry.

In 2003, BYD acquired Qinchi Automobile and began to produce cars. After about five years of research and development and learning, knowing both cause and effect, BYD started to inject innovative car-making ideas in 2008.

A landmark move was the launch of the F3DM, the world’s first plug-in hybrid vehicle.

Starting with “electricity,” BYD continuously changes the face of automobiles, from power batteries to power systems, from vehicle electronics to onboard devices, and even upended the European and American automotive “masters” by developing its first plug-in hybrid dedicated engine with a thermal efficiency of up to 43.04%.

Why can BYD do this?”BYD is a technology-driven enterprise that firmly believes that technology can change the world,” said Wang Chuanfu. Buffett’s initial investment in BYD was also driven by seeing Wang Chuanfu as another Edison.

Over the past 20 years, BYD’s success in batteries, electronics, mobile phones, and automobiles has convinced Wang Chuanfu that young Chinese engineers can defeat experienced European and American technology experts. He is also actively building and cultivating an engineer team.

According to the 2020 annual report, BYD has 35,800 R&D personnel, accounting for 15.95% of the total workforce. Considering BYD’s large manufacturing business, this proportion is quite high. In addition, R&D investment was 8.5 billion yuan, accounting for 5.46% of operating income. Among the listed Chinese automakers, BYD ranked second in R&D investment in 2020. Except for the new car forces, BYD also ranked second in R&D investment.

“Over the past 20 years, we have always been driven by technological innovation, and have always regarded our 30,000+ technical engineers as the group’s most valuable asset,” said Wang Chuanfu.

In terms of R&D, BYD has also introduced many international talents, formed international teams, and further strengthened its technical competitiveness. Some of the more prominent teams include the German chassis engineering team, responsible for chassis design and tuning, greatly improving ride comfort and handling capabilities; and the Japanese body team, responsible for body development, lightweighting, and mold manufacturing.

In addition, BYD also collaborates with international car companies for R&D and production.

In 2010, BYD established a joint venture with Daimler to build the DENZA brand electric vehicle.

In 2019, BYD and Toyota established a pure electric vehicle R&D company to carry out related business such as the design and development of pure electric vehicles and the platform and parts used in the vehicles.

BYD’s emphasis on technology at all levels has enabled the company to continuously break through and innovate. This has been BYD’s tactic since its inception.

The Green Technology Sword is Dancing

Since its establishment in 1995, more and more people have seen BYD’s presence. Wherever BYD goes, it often creates new value and products with innovative technologies.

At the same time, wherever BYD goes, it is also often challenged by reducing carbon dioxide emissions and sustainable development.

BYD currently has four major business segments: automobiles, rail transportation, new energy, and electronics. Among them, the automobile, rail transportation, and new energy industries are closely related to carbon reduction and sustainable development, and BYD has made outstanding achievements in all of these areas.BYD is the most recognizable car brand among ordinary people. In this field, BYD has mastered the core technologies of new energy vehicles such as batteries, motors, and electronic control, developed two major product lines for passenger and commercial vehicles, covering seven conventional fields and four special fields (i.e. the “7+4” strategy, in which “7” refers to private cars, taxis, urban buses, road passenger transport, urban commodity logistics, urban building logistics, and sanitation cars; “4” refers to warehouse, port, airport, and mining special vehicles), achieving full coverage across all fields. In May 2021, BYD announced the completion of the production and sale of one million new energy vehicles, making it the first Chinese and second global car maker to achieve this milestone.

In the field of rail transit, in October 2016, BYD launched the rail transit industry sub-brand, “SkyRail”. SkyRail has a short construction cycle, low noise, good landscape, and higher degree of integration with the city. It is also a completely zero-emission product.

In the field of new energy, BYD’s products cover consumer 3C batteries, power batteries (lithium iron phosphate batteries and ternary batteries), solar cells, and energy storage batteries, forming a complete battery industry chain. BYD is a leading global supplier of solar and energy storage solutions, and its products have been exported to many countries and regions such as the United States, Germany, Japan, Switzerland, Canada, Australia, and South Africa, helping more and more people achieve clean power generation and consumption.

BYD also attaches great importance to its own carbon emissions and sustainable development. At the recently held fourth China International Import Expo, BYD announced that it had received the first SGS Commitment to Carbon Neutrality Declaration certificate in China. This marks the recognition of BYD’s efforts in carbon neutrality in 2021 by an international authoritative organization. In August of this year, BYD also announced the creation of China’s first zero-carbon park headquarters, and promised to complete it in 2022.

Because BYD constantly strives to promote sustainable development of human society through technological innovation and helps achieve the “peak and carbon neutrality” goals, it was awarded the first-ever United Nations Special Energy Award for the new energy industry in 2015. BYD also won the Large Enterprise Award at the Zayed Future Energy Prize in 2016.

In mid-November, news came that at the COP26 climate conference, six global car manufacturers had pledged to gradually stop producing fossil fuel vehicles worldwide by 2040 to ease global warming. The six companies are General Motors, Ford, Mercedes-Benz, Volvo, Jaguar Land Rover, and China’s BYD.

This article is a translation by ChatGPT of a Chinese report from 42HOW. If you have any questions about it, please email bd@42how.com.