Ternary lithium battery or 48V lithium iron battery are named after positive active materials. This paper summarizes six common types of lithium batteries and their main performance parameters. As we all know, the specific parameters of the electric core with the same technical route are not exactly the same. What is shown in this paper is the general level of the current parameters. The six types of lithium batteries specifically include lithium cobalate (LiCoO2), lithium manganate (LiMn2O4), lithium nickel cobalt manganate (LiNiMnCoO2 or NMC), lithium nickel cobalt aluminate (LiNiCoAlO2 or NCA), lithium iron phosphate (LiFePO4), and lithium titanate (Li4Ti5O12).
The common nickel cobalt manganese acid lithium battery has a voltage of 3.7V and a capacity of about 2000mAh, while the iron lithium battery 26650 has a voltage of 3.2V and a capacity of 3000mAh,
2. Battery: the voltage shall be the same as the operating voltage of the motor, or slightly higher than the motor voltage.
3. The capacity of the battery is in AH. At the same voltage, the capacity is large and the volume is large. For example, if the working current of the motor is 10A and the voltage is 12V, then 10A * 12V=120W. If 12V/10AH battery motor is used, the working time is 1 hour.
4. The rated working current of the 120W12V DC motor is about 10A. The battery with the maximum power of 120W for 20 minutes has a storage capacity of 40Wh. The required capacity of the 48v battery pack is about 12V4Ah. The lithium battery is a power type battery.
5. The recommended combination is a lithium manganese polymer battery with a single cell capacity of 4-5Ah, three in series, a working voltage of 3 * 3.7V=11.1V, and a battery weight of about 100-200g. The lithium battery used in series shall be provided with a protective plate.
If the 48v lithium battery is fully charged, the difference of 1% will not affect the time for a few minutes, so there is no need to pay attention.
When designers design schemes, they leave room. The lithium battery is fully charged. Generally, the charging current of 4.35V (formerly 4.20V) is less than 0.05C. It is difficult to achieve in the actual use environment.
For example, your mobile phone uses a 4000mAh 4.35V lithium battery, which is theoretically required to be fully charged until 4.35V20mA. The sampling resistor on the motherboard is generally a precision resistor of 10 milliohms. Several million mainboards are produced at a time, and the resistance is always beyond the standard
In fact, during mass production, the software is always set to charge to 4.18V, and your phone's display interface will be 100% full. Prevent errors from causing user problems.
The software samples 2.90V-4.35V voltage range. If it is lower than 3.10V, it will alarm and shut down. It will not let you use 2.90V. When it is charged to 4.18V, it indicates that it is fully charged. In fact, it can be charged for more than ten minutes, and the charging current will be reduced to 30-50mA
The error of the cell phone's power calculation is at least 5%, which is not very accurate.
The external temperature is 30 ℃ in summer, - 10 ℃ in winter, and the temperature difference is 40 ℃. The 40 ℃ temperature difference causes the temperature drift of the sampling resistance to be 5%. There's no way
If the lithium battery is used in an environment higher than the specified operating temperature, that is, above 35 ° C, the battery power will continue to decrease, that is, the battery power supply time will not be as long as usual. If the device needs to be charged at this temperature, the damage to the battery will be greater. Even if the battery is stored in a hot environment, it will inevitably cause corresponding damage to the quality of the battery. Therefore, it is a good way to prolong the life of lithium battery to keep it at an appropriate operating temperature.
If 48v lithium batteries are used in a low temperature environment, that is, below 4 ° C, the battery life is also reduced, and the original lithium batteries of some mobile phones cannot even be charged in a low temperature environment. But don't worry too much. This is just a temporary situation, different from the use in high temperature environment. Once the temperature rises, the molecules in the battery will be heated, and the battery will recover its previous power immediately.
The life of lithium battery is generally 300-500 charging cycles. Assuming that the power provided by a complete discharge is 1Q, if the reduction of power after each charging cycle is not considered, the 48V lifepo4 lithium battery can provide or supplement 300Q-500Q of power in total during its life. It is known that if 1/2 is used each time, it can be charged 600-1000 times; If you use 1/3 of it every time, you can charge 900-1500 times. By analogy, if the battery is charged randomly, the number of times is uncertain. In a word, no matter how you charge it, the total power added is 300Q-500Q, which is constant.
The index reflecting the battery capacity, for example, 48V 100Ah indicates that the battery capacity is 4.8 kilowatt hours
The monomer voltage mainly depends on the type of monomer positive and negative electrode materials. The general lithium cobalate, ternary positive pole and graphite negative pole can obtain a full charge voltage of about 4.2V, while lithium iron phosphate can only reach 3.6V at most. The voltage here, to be exact, should be that the potential depends on the material properties, and the potential value is equal to the open circuit voltage of the battery after it has been left standing for a long enough time.