Electronic components. According to Zhihu's request, the 5-string lithium battery charging management chip is an electronic component used to manage the charging process of 5 lithium batteries connected in series to ensure their safety and charging efficiency. This chip contains several functional modules, such as voltage detection and current detection.
How to charge two 18650 lithium batteries at 5V, charging circuit
Question 1: What type of battery is good for a power bank From a structural point of view, the full name of? The lithium polymer battery must be a lithium ion polymer battery, in this way, the lithium polymer battery is actually a type of lithium ion battery. But the biggest difference between the two is the electrolyte used inside. Lithium-ion batteries use liquid electrolytes, while lithium-ion polymer batteries useent in place of solid polymer electrolytes. This polymer can be solid or semi-solid (colloidal).
Cylindrical lithium-ion battery
Secondly, in terms of appearance, most mobile power supplies currently on the market use cylindrical lithium-ion batteries or packs (that is, i.e. 18650). lithium polymer batteries. Therefore, when we choose a mobile power supply, if the outer packaging of the product does not specifically indicate the type of battery cells used, we can just get a rough idea of the type of battery used inside the product through the thickness of the product itself.
Lithium-ion batteries with excellent value for money
Lithium-ion batteries are improved products of lithium batteries. Because the chemical properties of lithium metal are very active, early lithium batteries often burn and. other situations may ariseproduce. In order to suppress the active chemical properties of metallic lithium, people added cobalt, manganese and other metallic materials to the cathode material of lithium batteries, which greatly improved the safety factor of early lithium batteries.
It can be said that after years of development, lithium-ion battery technology has become relatively mature, and mass production has made its manufacturing cost very low. Therefore, lithium-ion batteries have more price advantages than lithium-polymer batteries. This is why most laptops and other devices currently use this type of battery cell.
Since lithium ions using liquid electrolytes will suddenly increase their internal pressure when overcharged (overcharging), in order to avoid the explosion of the sealed metal case, usually this batterye 18650. Each battery will be equipped with a safety valve. on the top When the internal pressure of the battery is too high, the safety valve on the top will automatically pop up to reduce the pressure. However, when the safety valve opens, the lithium ions escaping from the battery can still catch fire due to contact with oxygen in the air.
Therefore, electronic products using this type of lithium-ion battery have very high requirements regarding their internal integrated charge and discharge protection circuits. However, with the years of development of lithium-ion batteries, both the design of the battery itself and the technical level of various protection integrated circuits have become very mature. As long as we can use it correctly and properly in daily life,To prevent the battery from being pierced by hard objects, the battery cell 18650 is still very safe, otherwise most laptops on the market would not use this type of battery.
Higher energy density lithium polymer batteries
Compared to lithium ion batteries using liquid electrolytes, lithium polymer batteries using solid polymer electrolytes have a unique shape. They have the characteristics of ultra-thin. , the theoretical minimum thickness can reach 0.5mm, and the characteristics of arbitrary shape and arbitrary area. It greatly improves the flexibility of the battery shape, so that it can be better transformed into a new generation of lithium batteries of any shape and capacity.
Lithium polymer batteries
In addition, lithium polymer batteries using solid polymer electrolytes have a higher energy density than ordinary lithium-ion batteries, i.e. -say in the same volume,Lithium polymer batteries have the advantages of lighter weight and higher capacity.
Lithium polymer batteries are thinner and lighter.
Strictly speaking, lithium polymer batteries are different from lithium-ion batteries using liquid electrolytes due to the positive electrode, negative electrode and electrolyte. as an operating principle. The only difference is in the separation and packaging materials. Therefore, basically lithium polymer batteries are also a type of lithium ion batteries.
Therefore, lithium-ion batteries in different packaging forms have the following characteristics:
Steel-cased lithium-ion batteries:
The The most common are those using steel. The 18650 battery in the shell has a high safety factor, the production technology is very mature and the pricex is cheaper than polymer batteries. It occupies the majority of the lithium battery market share and is most common in laptop batteries. .
Soft lithium-ion battery (polymer battery):
It has the characteristics of higher energy density, better safety performance and arbitrary shape, and has become the most common digital product. At present, the preferred battery cell, but compared with steel-cased lithium-ion batteries, the price is still high.
Summary: In fact, whether it is a steel case lithium ion battery or a soft pack lithium ion battery, the safety performance is very good . After all, current production. Lithium-ion battery technology is very mature. As long as high temperature, short circuit, overload, puncture, etc. are avoided. when used quotidienne can avoid what we call "explosion"... >>
Question 2: Which battery is best for power bank? It is an upgraded lithium-ion battery product. Compared with currently popular lithium-ion batteries, it has the advantages of large capacity, small size (thin) and safety (will not explode). The price is higher than usual.
Question 3: Which battery is best for power banks? Generally speaking, polymer batteries are better than 18650 batteries, but there are also good quality 18650 batteries. Yes, my power bank is from DOCA. The battery cells are original imported Samsung batteries. I have been using them for over two years and the quality is excellent.
Question 4: What does the battery capacity of a power bank mean? One of the important performance indicators of theBattery performance is the capacity of the battery, which indicates that under certain conditions (discharge rate, temperature, termination voltage, etc.) the amount of electricity released by the battery (JS-150D can be used for discharge tests), that is to say the capacity of the battery, generally in ampere-hours (abbreviated, expressed in A?H, 1A?h=3600C) Formula for calculating the capacity of the battery C C' is C=∫t0It1dt (integrate current I from t0 to t1 The battery is divided into positive and negative poles).
For example, if your mobile phone is 3000 mAh and the external battery is 10000 mAh, it can probably charge the phone three times
Question 5: How to use power bank What is the real meaning of battery? Power banks basically use lithium polymer batteries as energy storage units. It is itself a data storage device.lithium polymer battery energy. The voltage is regulated through the IC chip, then the stored energy can be released by connecting the power cord to charge or store energy.
Question 6: Which is better, polymer power bank or regular power bank? The lithium polymer battery has a larger capacity than the lithium battery in the same volume, and there is no memory. effect at all (lithium ion The battery still has a memory effect, it's just smaller). Lithium polymer battery is actually a gel-like substance that is easy to process into various shapes and does not contain harmful heavy metal elements. This is a “green battery”.
Ordinary power bank battery: Lithium-ion battery, commonly known as "lithium battery", is currently the battery system with the best overall performance. The negative electrode of the batterys lithium-ion is a carbon material, such as graphite. The positive electrode is a transition metal oxide containing lithium
Lithium polymer battery: Lithium polymer battery is a new generation battery that entered the market in large quantities in 1999. Lithium polymer batteries are basically the same as lithium ion batteries, except that the electrolyte is a solid polymer instead of a liquid electrolyte.
The basic components of mobile power supplies mainly have two parts , one is the storage medium. energy, and the other is It is the medium that converts the other energy into electricity. Since many customers wonder which brand of mobile power is good, the quality of the battery core can be one of the important criteria for measuring the quality of mobile power. Three commonly used power bank batteries includelithium polymer batteries, 18650 lithium batteries and AAA nickel-metal hydride batteries.
Lithium-ion polymer battery cells are more expensive than regular lithium-ion battery cells. However, the advantages of large capacity and small size of high-capacity lithium polymer batteries enable them to gradually replace ordinary lithium batteries.
According to the national standards of batteries, especially polymer batteries, there is a strict rating system that divides the quality and speed of batteries into three levels: A, B and C. A battery is a new polymer battery, battery B is a battery that has been in stock for more than three months or has been disassembled, and battery C is a used battery.Pool. It should be noted that although C electricity is cheap, it has serious quality problems. Electricity B is relatively cheap mbut decreases very quickly. If your finances permit, please purchase a power bank powered by A.
Question 7: For mobile phone power banks, which battery is best? . There is no advantage.
Failure to use the original charging equipment may result in the following consequences:
1. Shorten the life of the mobile phone
2. Damage the mobile phone;
3. The phone heats up when charging and burns the phone;
4. It loses power when charging
5. The screen flickers when charging; .
Therefore, users are recommended to stick to the original devices, whether it is Apple or other mobile phones or other devices.
Question 8: What is the difference between lithium polymer batteries and ordinary power bank batteries? The differencesences between lithium polymer batteries and ordinary power bank batteries are as follows:
1. Ordinary power bank: Lithium ion battery, commonly known as "lithium battery", is currently the battery system offering the best overall performance. The negative electrode of lithium-ion batteries is a carbon material, such as graphite. The positive electrode is a transition metal oxide containing lithium.
2. Lithium polymer batteries: Lithium polymer batteries are a new generation of batteries that entered the market in large quantities in 1999. Lithium polymer batteries are basically the same as lithium batteries -ion, except that the electrolyte is a solid polymer instead of a liquid electrolyte.
3. Lithium polymer batteries have a larger capacity than lithium batteries in the same volume, and there is no memory effecte (lithium-ion batteries still have a memory effect, but they are smaller). Lithium polymer battery is actually a gel-like substance that is easy to process into various shapes and does not contain harmful heavy metal elements. This is a “green battery”.
Question 9: What types of batteries are used in conventional power banks? There are two types. One is a battery with 18650 cells. It's cheap, but in theory there is a battery. possibility of leak. One is the lithium polymer battery, which is expensive but relatively safe. If you find my answer helpful, please hit the Like button, thank you!
Question 10: What is the difference between power bank lithium batteries and lithium polymer batteries? Lithium batteries are divided into liquid lithium batteries and lithium polymer batteries? The batterylithium polymer is an improved product of lithium-ion battery. Compared with currently popular lithium-ion batteries, it has the advantages of large capacity, small size (thin) and safety (will not explode).
The platform voltage of two lithium batteries is 7.4 V. I have never seen a low voltage battery used to charge a high voltage battery. If so, that would be amazing. To charge two batteries, the only way is to increase the voltage at the front, which is a booster board device. There is no other way than this. If you are just a personal use, you can buy a small booster board from Alibaba, adjust it to 8.4V (refer to the lithium battery charging voltage) and connect this board instead loading if you want to make a product, I suggest you; Leave it to the professionals. They will take into account voltage, current, temperature andpossible accidents so that you can sell the product with confidence.