The 48v 20A lithium battery requires 11 cells.
Since the rated voltage of a single lithium battery is 4.2V and 11 cells connected in series are 46.2V, the full voltage should be able to reach more than 50V .Series connection is one of the basic ways of connecting components in a circuit. Connect the circuit components end to end one by one. A circuit formed by connecting electrical devices in series is called a series circuit. The current flowing through each electrical device in a series circuit is equal.
Detailed information
Main characteristics of battery cells:
Small particle size, large specific surface area, white color, high purity, chemical properties are significantly improved. It can be used in lithium titanate battery materials and lithium cobalt oxide battery materials.
1.It shows the typical behavior of Faraday pseudocapacitance in the potential range of -0.05 ~ 0.35 V (vs SCE). The pseudo capacitor is a pseudo capacitor developed after the electric double layer capacitor.
Pseudocapacitance is also called Faraday quasicapacitance. For the Faraday quasi-capacity,
the charge storage process includes not only the storage on the electrical double layer, but also the activity of it. ions in the electrolyte at the electrode. Charge is stored in the electrode due to redox reactions in the substance. To put it more clearly, the pseudocapacitance is just countless small electric double-layer capacitors.
2. Under the same current density (mA/cm2), increase the specific capacitance (F/g).
3. Reduce the self-discharge rate and have a good service life.
Baidu Encyclopedia-Battery Cell
Why the prices of asame lithium battery do they vary greatly
It depends on the 18650 battery Feature. 18650 is only the appearance size of a battery and does not determine the battery type. Different types of batteries have very different charging and discharging characteristics.
The meaning of 18650 means that the battery diameter is 18mm and the height is 65mm. The last number 0 means that it is a cylindrical battery. ?However, common 18650 lithium batteries are now divided into ordinary ternary lithium ion batteries (and ternary lithium batteries also have a variety of subdivided models), lithium iron phosphate batteries and lithium titanate batteries. etc. ?
The rated voltage of ordinary ternary lithium ion batteries is 3.6-3.7V, and the charging cut-off voltage is 4.2V. The rated voltage of lithium iron batteries phosphate is 3,2 V and charging. the cut-off voltage is 3.6V, while the rated voltage of lithium titanate battery is the lowest, generally between 2.3-2.4V, and the energy density of the battery is also the highest weak.
However, it is the latest generation of batteries with extremely excellent performance, with fast charging and high current discharging capabilities, especially good low temperature characteristics and explosion-proof performance , and a lifespan of more than 10,000 times. These are traditional ternary lithium batteries that are second to none. The capacity of 18650 lithium battery is generally 1000 mAh to 3600 mAh. ?
Currently the most on the market is ternary lithium battery, followed by lithium iron phosphate battery, and lithium titanate battery is the smallest and most expensive. Except for lithium batteriestitanate, ordinary ternary batteries and lithium iron phosphate batteries can only be charged with conventional charging current. Generally, the charge rate of lithium batteries is 0.5.
In other words, theoretically, the charge is completed in 2 hours. Then, corresponding to a 2Ah battery, the maximum safe charging current is 1A. Of course, if the charger is better, plus a complete protection circuit. can also increase the charging current appropriately.
Detailed information:
Lithium batteries are labeled 3.7 V or 4.2 V. It's just that the manufacturer's labeling is different. 3.7V refers to the platform voltage (i.e. typical voltage) of battery discharge during use, while 4.2V refers to the voltage when it is completely charged.
Common rechargeable 18650 lithium batteries have a standard voltage of 3.6 or 3.7 V. When fully charged, it is 4.2 V. This does not matter much. something to do with the power (capacity) of 18650 batteries. from 1800 mAh to 2600 mAh, the main capacity is even marked 3500 or 4000 mAh or more.
It is generally believed that when the no-load voltage of a lithium battery is lower than 3.0V, it is considered exhausted (the specific value depends on the threshold value of the battery protection board). battery, such as as low as 2.8 V and 3.2 V). Most lithium batteries cannot discharge their no-load voltage below 3.2V. Otherwise, over-discharging will damage the battery (generally, lithium batteries on the market are mainly used with a protection plate, so over discharge will also prevent the protection plate from detecting the battery,which will make it impossible to charge the battery).
4.2 V is the maximum limit voltage for battery charging. It is generally believed that the lithium battery is fully charged when its no-load voltage reaches 4.2V. During the battery charging process, the battery voltage gradually increases. from 3.7V to 4.2V. When charging lithium batteries, the no-load voltage cannot be charged above 4.2V, otherwise the battery will be damaged. This is the particularity of lithium batteries.
Baidu Encyclopedia - 18650
Baidu Encyclopedia - lithium battery
How to calculate the charging current that the battery cell can withstand< /h3> < p>
The reasons are:
1. Selecting cells with different material systems will affect the price of the entire lithium-ion battery. Depending on the cathode material, lithium-ion batteries include manganalithium te (3.6 V), lithium-cobalt oxide (3.7 V/3.8 V), lithium-nickel-cobalt manganate (commonly called ternary, 3.6 V) and phosphate iron and lithium (3.2 V). ). ), lithium titanate (2.3V/2.4V) and other battery cores of various hardware systems.
Battery cells with different material systems have voltage platforms, safety factors, cycle counts, energy density ratios, operating temperatures, etc.
2. The price of battery cells from different brands will also vary greatly. The price difference of battery cells of the same hardware system but different brands will also be very large, each battery cell brand has it. been eliminated thanks to the survival of the fittest in the market. Quality (security, consistency, stability) is fundamentally proportional to price.
3. Ability. If there is no virtual standard forthe capacity of the lithium-ion battery, generally, the larger the capacity of the battery, the higher the price will be.
4. Protection board quality and circuit design. Good quality lithium-ion batteries use high-quality electronic components and protection boards, and also have multiple protection circuit designs. They not only improve charging and discharging circuits, but also have multiple designs such as constant temperature and constant voltage, overcharge, overcharge. -discharge, overcurrent, short circuit, etc. Create a safe environment for you and your device.
However, these low-cost lithium-ion batteries do not have perfect production technology, and their safety cannot be guaranteed. Therefore, when choosing, you should choose a lithium-ion battery manufacturer of reliable quality.
When there is no novirtual rm regarding the capacity of lithium-ion batteries, generally, the larger the capacity of the battery, the higher the price will be.
Early R&D
Lithium batteries were first used in pacemakers. Lithium batteries have the advantages of extremely low self-discharge rate and gentle discharge voltage, allowing pacemakers implanted in the human body to work for a long time without recharging. Lithium batteries typically have a voltage rating above 3.0 volts and are best suited for use as an integrated circuit power supply. Manganese dioxide batteries are widely used in calculators, digital cameras and watches.
In order to develop more efficient varieties, various materials were researched to create unprecedented products.
In 1992, Sony successfully developed batterieslithium-ion. Its practicality has significantly reduced the weight and volume of portable electronic devices such as cell phones, laptops and calculators.
Reference for the above content: Baidu Encyclopedia - Lithium Battery
Charging current is equal to the battery capacity divided by ten.
For example, if there is a battery with a capacity of 1500 mAh, its normal charging current is 1500÷10=150 mA. Normal full charge time is 12-14 hours.
Working principle: When charging, external electrical energy is used to regenerate internal active materials, and the electrical energy is stored as chemical energy. When it needs to be discharged, the chemical energy is converted into electrical energy. output again, such as mobile phone batteries commonly used in daily life.
Uselization and cell characteristics
Refers to a single electrochemical cell containing positive and negative electrodes, which is generally not used directly. Different from the battery, it contains a protection circuit and a shell and can be used directly.
The composition of a lithium-ion rechargeable secondary battery is a battery cell + a protection circuit board. The rechargeable battery removes the protective circuit board and becomes the battery core. This is the electricity storage part of the rechargeable battery. The quality of the battery core directly determines the quality of the rechargeable battery.
Battery cells are divided into three types: aluminum shell batteries, soft package batteries, also called polymer batteries, and cylindrical batteries. Usually cell phone batteries use batries with aluminum shell, digital products such as Bluetooth mainly use soft batteries, and laptop batteries use a series-parallel combination of cylindrical batteries. The particle size is small, the specific surface area is large, the color is white, the purity is high, and the electrochemical performance is greatly improved.
Can be used in lithium titanate battery materials and lithium cobalt oxide battery materials. It exhibits typical Faraday pseudocapacitive behavior in the potential range.