Why is there no No. 4 for the battery model?

China is named after international practice, and the cylindrical battery model is classified as:

AAA, AA, A, SC, C, D, F types, a total of seven types.

No. 5 and No. 7 are just different in size, generally No. 5 is called AA, No. 7 is called AAA, and the standard size of No. 5 is: battery height, diameter.

The standard dimensions of size 7 are: battery height, diameter.

There are dry batteries, lithium batteries, nickel-metal hydride batteries and nickel-cadmium batteries made into No. 5 and No. 7.

Common alkaline batteries (such as Nanfu Energy Ring, Duracell, etc.) have No. 5 and No. 7 voltages, with a capacity of about 2400mAh for No. 5, also known as LR06, and No. 7 for about 1300mAhAlso called LR03.

In fact, there are other types of batteries, such as: No. 1 (type D), battery height, diameter, like the old flashlight used in the past, also called large battery.

There is also No. 2: type C, battery height, diameter, this is relatively rare, but some lithium batteries are generally divided into numbers, of which No. 5 and No. 7 are particularly commonly used, the so-called AA battery is the No. 5 battery, and the AAA battery is the No. 7 battery! AA and AAA both indicate the battery model.

For example, AA is what we usually call a No. 5 battery, with a general size of 14mm in diameter and 49mm in height;

AAA is what we usually call a No. 7 battery, and the general size is: diameter 11mm, height 44mm.

The following is from this site: NiMH battery forum netizens added.

There are also a number of battery knowledge:

Let's talk about the common models of "aaaa, aaa, aa, a, sc, c, d, n, f".

AAAA models are rare, and disposable AAAA Energizer alkaline batteries can still be seen occasionally, which are generally used in computer pens. Standard AAAA (flat head) battery height, diameter.

AAA type batteries are more common, and the general ones are AAA batteries, standard AAA (flat head) battery height and diameter.

AA model batteries are even more well-known, digital cameras, electric toys are indispensable AA batteries, standard AA (flat head) battery height, diameter.

Only one A means that the model of the battery is not common, this series is usually used as the battery cell in the battery pack, I often change the nickel-cadmium and nickel-metal hydride batteries of old cameras for others, almost all of them are 4 5A, or 4 5SC battery cells. Standard A (flat head) cell height, diameter.

SC models are also not common, generally the battery cells in the battery pack, which can be seen in power tools and cameras and imported equipment, and the standard SC (flat head) battery height and diameter.

Model C is the No. 2 battery, which has many uses, and the standard C (flat head) battery height and diameter.

Hope my answer will help you solve the problem!!

Because no manufacturer needs a No. 4 battery to make something, if there is, there will be a No. 4 battery.

The No. 3 battery, also known as the SC type battery, is 51mm high and diameter, thicker than the No. 5 battery, and is used for rechargeable battery packs.

No. 4 battery, also known as A-type battery, is 49mm high and diameter, and is used for rechargeable battery packs.

Other battery sizes.

1. AA type 2 battery (No. 8 battery LR1 AM5) diameter; Height.

2. AAAA type battery (No. 9 battery LR61 AM6) diameter; Height.

3. AAAA type 2 battery (small No. 9 battery LR61 AM6) diameter; Height.

These two types of batteries are easy to distinguish, the No. 5 battery is larger, and the No. 7 battery is smaller. No. 5 or No. 7 batteries are marked on the outer packaging, and No. 5 batteries are a little larger than No. 7.

A battery is a device that converts chemical energy into electrical energy in a cup, tank, or other container or composite container that contains an electrolyte solution and metal electrodes to generate an electric current. It has a positive electrode and a negative electrode. With the advancement of technology, batteries generally refer to small devices that can generate electrical energy.

Such as solar cells. The performance parameters of the battery mainly include electromotive force, capacity, specific energy and resistance. Using the battery as energy, you can get a stable voltage, stable current, long-term stable power supply, little influence from the outside world, and the battery structure is simple, easy to carry, simple and easy to charge and discharge, not affected by the outside climate and temperature, stable and reliable performance, and plays a great role in all aspects of modern social life.

In 1746, Massenbrock of Leiden University in the Netherlands invented the "Leiden bottle" to collect electric charges. Because he saw that the electricity that he had collected with great difficulty was easily disappearing in the air, he wanted to find a way to preserve it.

One day, he hung the barrel of a gun in the air, connected to the barrel with a motor, and a copper wire was drawn out of the barrel and immersed in a glass bottle filled with water, and he asked an assistant to hold the glass bottle in one hand, while Massenbrock shook the motor vigorously.

At this time, his assistant accidentally touched the barrel of his other hand, and he suddenly felt a strong electric shock and shouted. Massenbrock then swapped with his assistant, asking him to shake the motor, holding the water bottle in one hand and touching the barrel with the other.

There is no No. 4 battery, so I can't compare the size. The No. 3 battery is larger than the No. 5 battery.

Batteries are generally divided into numbers, of which No. 5 and No. 7 are particularly commonly used. AA is what we usually call No. 5 battery, the general size is: diameter 14mm, height 49mm; AAA is what we usually call a No. 7 battery, and the general size is:

Diameter 11mm, height 44mm.

Precautions for battery use:

1) Regularly check the position of the liquid level of the electrolyte, please replenish it immediately when it is lower than the minimum liquid level scale line, if you continue to use it in this state, it will not only accelerate the aging of the internal parts of the battery, shorten the service life of the battery, but also may cause **.

2) Do not place the battery near an open flame (matches, lighters, lit cigarettes, etc.), and do not cause sparks caused by short circuits in the wires near the battery.

3) When charging the battery, please read the warning plate of the battery carefully and remove the battery from the machine.

4) The electrolyte (dilute sulfuric acid) of the battery is corrosive and cannot be directly contacted. Once the eyes, **, and clothes are stained with electrolyte, please wash them thoroughly with water immediately, and if the electrolyte enters the eyes, in addition to washing them with water immediately, you should also go to the hospital for necessary **.

5) Regularly maintain and maintain the battery.

The most obvious feature is the size, the No. 5 battery is larger than the No. 7 battery. Common battery models and size correspondence No. 7 battery size is a little smaller than No. 5 battery, mostly used in remote control and other occasions where the volume is limited but the power consumption is not too large, flashlights are also used, but most of them are used in combination with multiple cells.

No. 5 battery is the type of battery, that is, the international standard.

There are relatively many types of No. 5 batteries, including alkaline No. 5 batteries, nickel-cadmium No. 5 batteries, nickel-metal hydride 5 good batteries, etc. The main thing is that the internal material is not the same. Among them, alkaline batteries are non-rechargeable, 3 5 collapses are alkaline non-rechargeable batteries, and nickel-cadmium batteries and nickel-metal hydride batteries are rechargeable batteries.

Rechargeable batteries have different capacity deficits, such as: 1800 mAh, 2000 mAh, 2300 mAh, 2500 mAh, 2700 mAh and so on. The higher the number of milliamps, the greater the capacitance and the longer the service life.