18650 batteries for laptops generally have a capacity of 2200 mAh (mAh), a voltage: 3.7 V
a current of 2200 mA (mA) and can be used for 1 hour (hour).
The highest specification capacities are 2400 mAh and 2600 mAh (most are Sanyo batteries and most Sony laptops use 2600 mAh specifications).
The following takes the common 3.7V/2200mAh battery cell as an example.
1. The battery commonly known as a three-cell battery is a battery made up of three 18650 cells connected in series. The final marked parameters of the battery are 11.1V/2200mAh. 11.1V = 3.7V × 3, the output current remains unchanged when connected in series.
There are also those marked 10.8 V, that is, a voltage drop occurs in a single cell, resulting in a reduction in the total voltage.
Most netbooks popular on the market are now equipped with batteries meeting this specification.
There are two situations for two-cell and four-cell batteries: four in series and two in series and two in parallel.
The last marked parameters of the four batteries connected in series are: 14.8V/2200mAh. 14.8V = 3.7V × 4. When connected in series, the output current remains unchanged at 2200mAh.
Two series and two parallel means that four batteries are divided into two groups. Two pairs are connected in series then in parallel. The final marked parameters of the battery are: 7.4V/4400mAh. 7.4V = 3.7V × 2, output current is 4400mAh = 2200mAh × 2.
Most mid-sized laptops (12.1 inch, 13 .3 inch, etc.) on the market now have batteries of this specification.
Detailed information:
Look at the number 18650. Actually it represents size 18 means the battery has a diameter of 18mm, 65 means that the length is 65mm and the last 0. means the battery is cylindrical in shape. There are generally three types of 18650 batteries: lithium-ion batteries, lithium iron phosphate batteries, and nickel-metal hydride batteries.
The 18650 standard is a standard-shaped lithium-ion battery model established by the Japanese company SONY in its early days to reduce costs.
Advantages:
① Large capacity: a lithium battery cell has at least 1200mah, even 3600mah, while ordinary battery cells only have 'about 500;
< p>② High energy storage efficiency and good stability: the full output power can be maintained in an environment of 70°, and there are generally internal protection circuits to prevent the batteryrun out③ There is almost no memory effect: during charging There is no need to discharge all the remaining power before use, it can be charged or discharged at any time, easy to use
④High charge and discharge cycle life: the number of cycles of lithium batteries; is highThousands of times and has good high temperature resistance;
⑤Environmental protection, no toxic substances: non-toxic, harmless, non-polluting, RoHS certified quality.
Lithium batteries are usually not used in one, but in several strands. We often call them batteries. This type of battery often appears in our daily life, such as our laptop batteries, external batteries and electronic batteries. . Wireless digital equipment for printer, portable products, intercom communications, lithium batteries for POS machines, andvs. At present, the base capacity of many batteries is 2200mah.
The following is the specification table of Sanyo brand lithium batteries. Generally, the best batteries have four main protection functions:
①Overcharge protection: When the lithium battery is overcharged When the overcharge voltage of the battery reaches a certain value or period of time, the function Overcharge protection will take effect and automatically stop charging to protect the battery;
② Over-discharge protection: Over-discharge means the battery is in a constant overcharge output state. Usually there is protection against discharge. At this time, the battery will be in standby mode;
③ Overcurrent Protection: This overcurrent protection value can adjust the number of amps for some things. choose setting en depending on the actual situation
④Short circuit protection; When the battery is short circuited, the overcurrent will act to protect the battery from burning.
In addition to these four protection functions, some also have temperature, equalization and other functions. The battery usually has a built-in PCM protection system with several protection functions.
Baidu Encyclopedia-18650 lithium battery
What is the reason why 18650 lithium battery cannot be charged and Solution
A battery consisting of several strings of cells must be protected against overcharging and overdischarging. The voltage of a single cell is not enough.
The principle of battery protection against overcharge and overdischarge is to prevent the voltage of each cell in the system from exceeding the operating range.normal operation. The most basic requirement is to have the tension of each string, and. then when a certain When the voltage of a battery cell exceeds the lower voltage limit or the upper voltage limit, it will be quickly prevented from continuing to discharge or charge, thereby playing a protective role.
Refer to the image below. The most important thing in this process is to collect the voltage from each cell chain. If you have a 2-string battery, you must have V1 and V2 voltage values. It is not enough to collect the value of V. If there is only the value of V, overloading or overdischarging a single string may occur unknowingly.
Solution: Replace it with a new battery.
Possible reasons why the battery cannot be charged:
1. Lithium battery suffers from external short circuit or overcharge, cReverse harge (forced overdischarge).
2. The battery is continuously overcharged by high and large current, which causes the battery core to expand and the positive and negative electrodes to directly contact and short circuit.
3. There is an internal short circuit or micro short circuit in the battery. For example, if the positive and negative electrode plates have burrs that penetrate the separator paper and cause a short circuit, improper battery placement. positive and negative electrode plates cause short circuit of the electrode plates, or short circuit of the positive electrode plate in contact with the steel housing, ear connection of the positive terminalThe part of the The negative electrode is short-circuited, the negative electrode powder falls into the separator paper, the separator paper itself is defective, etc.
Detailed information:
Notes:
1. Read the battery instructions carefully, use the recommended batteries, and operate according to the operating procedures.
2. Check whether the contact parts of the electrical appliance and the battery are clean. If necessary, wipe with a damp cloth.
3. Under adult supervision, do not allow children to change batteries. Small batteries such as AAA should be kept out of reach of children.
4. Do not mix new batteries, old batteries, or batteries of different types, including dry batteries and rechargeable batteries.
5. Do not heat the battery or put it in water or fire. Putting the battery in water will cause battery failure. Ignition will cause the battery to burst.