12.6 V for 3 cells, 16.8 V for 4 strings. Floating charge. Refers to recharging when working online. This method is often used in emergency power situations. It cannot be charged if it is lower than 12 volts and it will affect the operation of the circuit if it is too high. Therefore, when floating charging is working, the voltage is 13.8 volts.
Main principles
1. Lithium battery: It adopts a spiral winding structure and uses very thin and highly permeable polyethylene film insulation material to separate the positive and negative electrodes.
2. Dry battery: the carbon rod is used as the positive electrode and the zinc cylinder is used as the negative electrode, which converts chemical energy into electrical energy and supplies it to the external circuit. In chemical reactions, as zinc is more active than manganese, zinc loses electrons and oxidizes, while manganese gains electrons and is reduced.
The 12v to 50ah lithium battery represents: the battery operates at a current of 50A on a device with a voltage of 12V and can operate for 1 hour.
Ampere-hours (AH) represent the size of the battery capacity. For batteries of the same voltage, the one with the greater amp-hour has a greater capacity; For batteries with the same amp-hour, the one with the higher voltage has a greater capacity. Battery capacity is usually expressed in terms of voltage and amp hours. hours.
Detailed information:
Lithium battery characteristics:
1. High energy density
The weight of lithium-ion batteries is half that of nickel-cadmium or nickel-hydrogen batteries of the same capacity, and the volume is 20 to30% nickel-cadmium and 35 -50% nickel-hydrogen.
2. High voltage
The operating voltage of a lithium-ion battery cell is 3.7 V (on average), which is equivalent to three connected nickel-cadmium or nickel-metal hydride batteries. serial.
3. Pollution-free
Lithium-ion batteries do not contain harmful metal substances such as cadmium, lead and mercury.
4. Does not contain lithium metal
Lithium-ion batteries do not contain lithium metal, so they are not restricted by air transport regulations such as the ban on transporting lithium batteries on board passengers. plane.
5. High service life
Under normal conditions, the charge and discharge cycles of lithium-ion batteries can exceed 500 times, and lithium iron phosphate (hereinafter referred to as iron phosphate) can reach 2,000 second rate.
6. No memory effect
The memory effect refers to the phenomenon that the battery capacity decreases during the charge and discharge cycle of nickel-cadmium batteries. This effect does not exist with lithium-ion batteries.
7. Fast charging
Using a constant current and constant voltage charger with a rated voltage of 4.2V, the lithium-ion battery can be fully charged in 1.5-2.5 hours; and The new lithium iron phosphate battery can be fully charged in 35 minutes.
Baidu Encyclopedia-Lithium Battery