Lead batteries are widely used and extensively studied by all kinds of electric vehicles because of their cheap price, rich material sources, higher specific power, more mature technologies and manufacturing processes, and higher comprehensive resource recovery rates, battery tender for motorcycle.
As a labor-saving, convenient, fast, comfortable, cheap and zero-emission personal electric bicycle has been widely accepted by the people, and the attention of the relevant state departments. The research group “Strategic Research on the Development of Light-duty Electric Vehicles Industry” participated by the State Council Development Research Center, the National Development and Reform Commission, the Ministry of Construction and the Ministry of Science and Technology proposed the “Study on the Strategic Development of Light-duty Electric Vehicles Industry”. The national ownership of electric bicycles has reached 30 million or more. More than 95% of electric bicycles are using valve-regulated lead-acid batteries.
Comprehensive performance has greatly improved
The past 10 years, electric bicycle valve with lead-acid batteries have greatly improved the overall performance. Take a 6-DZM-10 battery as an example. In 1997, this type of battery has insufficient capacity, 2h rate (5A) discharge capacity of less than 10 Ah; specific energy, 2h rate than the energy of less than 30Wh / kg; short life expectancy, 100% depth of discharge cycle life of only 50 -60 times (capacity down to 8 Ah ago; the same below), the service life of only 3-5 months and other issues. By 2003, 2h rate (5A) discharge capacity reached 11–13Ah; 2h rate than the energy to reach 33–36 Wh / kg; 100% discharge depth of the cycle life of 250 — 300 times, the service life of up to 12 More than a month. Electric bicycle valve-regulated lead-acid battery problems have been basically solved.
The past two years, this type of battery life cycle performance of deep new breakthroughs. The main performances are as follows: the initial discharge capacity at 2h rate (5A) reaches 14Ah; the rate energy reaches 38 Wh / kg at 2h; the cycle life at 100% discharge depth exceeds 400 cycles with a total discharge capacity of 4500 Ah and a corresponding cumulative mileage of 18 000km (At 4 km / Ah, the same below). The highest deep cycle life of more than 600 times, the total discharge capacity of 6151 Ah, the corresponding cumulative mileage of about 24600km. If the capacity is less than 7 Ah end of life signs, deep cycle life of 943 cycles, release a total capacity of 8710 Ah, the corresponding cumulative mileage of about 34800 km. If you press the deep cycle life of 250 times or release the total capacity of 2 250 Ah, the corresponding cumulative mileage of 9 000 km battery pack can guarantee the use of 1 year, then this type of battery life of 2 years is not a dream.
Of course, the current production of electric bicycle valve regulated lead-acid batteries, about 200 manufacturers of the size, product quality varies, to capacity, energy, life expectancy (especially important) and other comprehensive indicators to meet the requirements of small manufacturers.
Attention and charger match
In many years of practice, the manufacturers of electric bicycles and battery manufacturers have gradually realized the importance of the matching between battery and electric drive system related equipment, especially with the charger. Manufacturing quality is a prerequisite for battery quality, but only with its matching charger to play the high-quality batteries should have the superior performance, or high-quality batteries cannot fully play its potential superior performance. Different manufacturers of batteries due to the formula, structure, acid concentration differences, the appropriate charging parameters are different. For example, we found in the study that different manufacturers’ batteries can have a charging voltage of 1.5-2.0 V (for a 36 V battery pack) at constant voltage. The basic parameters of the appropriate charging parameters are: to ensure that the battery is fully charged, will not be due to undercharged battery capacity caused by abnormal attenuation; but also, to ensure that the battery during life will not be overcharge caused by severe battery water loss and thermal runaway.