Will 12V lead-acid batteries soon exit the market?
That's right, 12V lead-acid batteries in cars are on their way out. Europe has decreed that all new vehicles will no longer use lead-acid batteries after 2030, presenting OEMs with a significant challenge to find alternative solutions. While this may seem like a daunting task, it can also give a huge opportunity to eliminate environmentally harmful batteries and reduce vehicle weight and improve overall efficiency.
The 12V battery and power Supply network (PDN) is a global standard that supports hundreds of loads, including some closely related to safety, so the solution must be both innovative and robust. The high density, high power and high-efficiency power modules used to connect high voltage, 48V and 12V PDN provide the most flexible and scalable solution to this emerging challenge.
When considering potential solutions, OEMs must consider several essential factors: increased power to support new features with better performance, improved efficiency to extend the range and optimize thermal management, reduced CO2, optimized cable wiring, reduced wire harness weight, and meeting EMI requirements. These are some of the variables in this complicated equation.
There are two main options for solving this equation. Replacing the 12V lead-acid battery with a 12V lithium-ion battery is an option. While it does offer a slight weight reduction, it will retain decades of 12V PDN tradition without any other advantages. Another option is to support a 12V PDN powered by a 400V or 800V main battery in electric vehicles and hybrids/plug-in hybrids. The latter option has many advantages, but both are worth exploring further.
Use 12V lithium ion battery
Simply replacing a 12V lead-acid battery with a 12V lithium-ion battery does save about 55% in weight, but the cost impact is high. 12V lithium-ion batteries require a battery management system (BMS) to control charging and keep the battery fully operational throughout the vehicle's life. This is where Tesla and Hyundai are headed.
In addition, a sizeable DC-DC converter (with voltage and current regulation) from high voltage to 12V would need to be added to charge the 12V Li-ion battery and power the electrical load. But this does not add any advantage. It adds weight, the complexity of the overall vehicle arrangement and system cost and reduces its overall reliability. By contrast, eliminating the 12V battery reduces vehicle weight by 13kg and increases cargo space by 2.4%.
