Batteries began to be used in automobiles in 1918, and gradually became popular in 1920, when the battery voltage was 6V.
Background
With the increase of internal combustion engine displacement and the emergence of high compression ratio internal combustion engines, the 6V starting battery system can no longer meet the demand, so the 12V starting system was adopted in 1950.
48V battery came into being
After the 12V voltage lead-acid battery is applied to the start-stop system of the car, it has basically reached the power output limit. If the mild-hybrid start-up system is operated at 12V voltage, the power requirement is about 10kW~15kW.
Under such a voltage, the output current of the battery needs to be as high as 1000A. Obviously, 12V lead-acid batteries can no longer meet such requirements.
In 2011, Audi, BMW, Daimler, Porsche, Volkswagen jointly launched a 48V vehicle starter battery system, and subsequently released the 48V vehicle starter battery system specification LV148 to meet the growing demand for vehicle battery loads, and more importantly, to meet the needs of 2020 strict emissions regulations that came into effect in 2018.
Why 48V?
Because 60V is a safe voltage, that is to say, as long as the voltage is lower than 60V, no additional safety precautions need to be taken.
The charging voltage of a 48V battery is up to 56V, which is very close to 60V, that is, the 48V battery voltage is the highest voltage level for operation at a safe voltage.
48V vehicle battery start-stop system has become the focus of the industry due to its significant energy saving and emission reduction advantages and limited cost increase
For full hybrid vehicles, the 48V on-board battery start-stop system can save 40%-60% of the cost, and the 48V lithium battery charging module can also improve the fuel efficiency by 10%-15%, which is an effective way to save energy.
