Is a nickel cadmium battery acidic or alkaline?

It's an alkaline battery!!

Alkaline batteries are divided into iron-nickel, cadmium-nickel, zinc-silver batteries and other series according to the active materials of the plates. The working principle of nickel-cadmium battery is: after the active material of the battery plate is charged, the positive plate is nickel hydroxide Ni(OH)3, and the negative plate is cadmium metal (Cd); At the end of the discharge, the positive plate is converted to nickel hydroxide Ni(OH2), the negative plate is converted to cadmium hydroxide CD(OH)2, and the electrolyte is mostly potassium hydroxide (KOH) solution.

In the process of charging and discharging.

From the chemical reaction during the charging and discharging process, it can be seen that the electrolyte only acts as a carrier of electric current and the concentration does not change, so it can only be judged according to the change of voltage.

The degree of charge and discharge. During the charging process of the nickel-cadmium sealed battery, oxygen is precipitated from the positive electrode and hydrogen is precipitated from the negative electrode. Because the negative electrode material of the cadmium-nickel sealed battery is too high during the manufacture, this avoids the occurrence of hydrogen; The oxygen generated on the positive electrode is absorbed by the negative electrode due to electrochemical action, thus preventing the gas from accumulating inside the battery, thus ensuring the normal operation of the battery under sealed conditions.

Nickel-cadmium batteries have been used for decades, originally used as traction, starting, lighting and signaling power sources, and now as starting and ignition power sources for diesel locomotives and aircraft. Sealed batteries made in the 60s were used as power sources for satellites, portable power tools, and emergency equipment. One of the directions of improvement of nickel-cadmium battery is the use of bipolar structure, which has very small internal resistance, is suitable for pulse high-current discharge, and can meet the power supply needs of high-power equipment; In addition, the electrodes are pressed, sintered, and foiled.

Nickel-cadmium batteries are alkaline and the battery liquid is a potassium hydroxide solution.

First, the genera are different.

1. Alkaline battery: It is the best variety of zinc-manganese battery series.

2. NiMH battery: It is a battery with good performance.

Second, the characteristics are different.

1. Alkaline batteries: The capacity of alkaline batteries is higher than that of carbon batteries, because manganese dioxide used as cathodes has a higher purity and same density, and the volume of internal parts is finer (such as electrodes), which also gives room for disadvantages, which helps to increase capacity, and in general has 3 to 5 times more capacity than carbon batteries.

2. NiMH battery: low-voltage NiMH battery has the following characteristics: the battery voltage is equivalent to that of cadmium-nickel battery; The energy density is high, which is more than twice that of nickel-cadmium batteries; It can be charged and discharged quickly, and has good low-temperature performance.

Nickel-cadmium battery (Ni-Cd battery) is a rechargeable battery composed of a nickel-metal hydride (NiMH) cathode, cadmium hydroxide (CD) anode, and an alkaline electrolyte.

Nickel-cadmium batteries have the following characteristics:

High cycle life: Nickel-cadmium batteries have a high charge-discharge cycle life, typically up to thousands of charge cycles.

Stable voltage output: Ni-cadmium batteries provide a relatively stable voltage output during discharge, which is suitable for applications that require stable voltage for a long time.

Good charging performance: Nickel-cadmium batteries have good charging performance and can be fully charged in a short time.

Good high temperature resistance: Nickel-cadmium batteries have good high temperature resistance characteristics and are suitable for applications in high temperature environments.

Higher energy density than spike rolling: Compared with some other rechargeable batteries, nickel-cadmium batteries have a higher energy density and are able to provide a longer service life.

However, there are also some shortcomings in the nickel hall good cadmium battery

There is a memory effect: If there are frequent incomplete charge-discharge cycles, nickel-cadmium batteries may have a memory effect, resulting in a decrease in usable capacity.

Chemical toxicity: Cadmium in nickel-cadmium batteries is a toxic substance that can cause harm to the environment and human health if not handled properly.

Low specific energy: Compared with some newer batteries, nickel-cadmium batteries have relatively low specific energy, limiting their application in specific fields.

Due to the environmental and health risks of nickel-cadmium batteries, as well as the limitation of energy density, they have been used by other types of rechargeable batteries, such as lithium-ion batteries and nickel-metal hydride batteries, in many applications.

For nickel-cadmium batteries, cadmium Cd is the negative electrode and NiO(OH) is the negative electrode.

Total reaction: 2NiO(OH)+CD+2H2O== Discharge==2Ni(OH)2+Cd(OH)2

Charging is written in reverse: 2Ni(OH)2+CD(OH)2== Charging core mu==2NiO(OH)+CD+2H2O

Positive electrode: 2NiO(OH)+2H2O+2 electron pie ===2Ni(OH)2+2OH- (OH- is hydroxide).

Negative modification: cd-2 electrons +2oh- = cd(oh)2

Generally speaking, "alkaline batteries" refers to a large categoryDisposable batteries (i.e., non-rechargeable batteries).。These batteries use alkaline substances such as KOH as the electrolyte component, hence the name.

NiMH batteries areRechargeable battery, i.e. secondary batteries. Therefore, it does not belong to the so-called "alkaline battery".

"Alkaline battery" is just a conventional name, strictly speaking, in fact, the electrolyte of carbon batteries, carbon batteries, nickel-cadmium batteries and nickel-metal hydride batteries are all alkaline.

Of course, there are two main differences between nickel-metal hydride batteries and lithium batteries, one is the battery voltage, the voltage of a single-cell nickel-metal hydride battery is, and the voltage of a single-cell lithium battery is; The second is the capacity, the same volume of nickel-metal hydride battery and lithium battery, the capacity of nickel-metal hydride battery is lower than the capacity of lithium battery. If you use it in a model airplane, it is recommended to use a lithium battery, because with two batteries of the same weight, the lithium battery can provide more power.

1. The battery material is different

1) The active material on the positive plate of the nickel-cadmium battery is composed of nickel oxide powder and graphite powder, and the main function of graphite is to enhance electrical conductivity. The active material on the negative plate is composed of cadmium oxide powder and iron oxide powder, the function of iron oxide powder is to make cadmium oxide powder have higher diffusion, prevent agglomeration, and increase the capacity of the plate.

2) The positive active material of the nickel-metal hydride battery is Ni(OH)2 (called the NIO electrode), the negative active material is metal hydride, also known as the hydrogen storage alloy (the electrode is called the hydrogen storage electrode), and the electrolyte is 6mol L potassium hydroxide solution.

2. Different classifications:

There are two types of nickel-metal hydride batteries: high-voltage nickel-metal hydride batteries and low-voltage nickel-metal hydride batteries. There is no other classification for nickel-cadmium batteries.

3. The requirements for charging and discharging are different

1) Nickel-cadmium batteries can withstand overcharging or over-discharge.

2) Do not overcharge the nickel-metal hydride battery during use, because overcharging is easy to expand the positive and negative electrodes, resulting in problems such as active material falling off and separator damage, damage to the conductive network and increasing the ohmic polarization of the battery.

4. The life span is different

1) Nickel-cadmium batteries can provide more than 500 times of charge and discharge cycles, and the life span is almost equal to the service life of the equipment using this kind of battery.

2) NiMH batteries have a long cycle life, up to thousands of times.

5. The specific characteristics are different

NiMH batteries have good specific characteristics. Its mass specific capacity is 60a·h kg, which is 5 times that of nickel-cadmium batteries.

Answer: NiMH battery is a replacement product for the early nickel-cadmium battery, it is the most environmentally friendly battery at present, no longer uses toxic cadmium, and can eliminate the pollution problem caused by heavy metal elements to the environment. NiMH batteries have a large energy density ratio, which means that the use of NiMH batteries can effectively extend the operating time of the equipment without adding extra weight to the digital device. Another advantage of NiMH batteries is:

The "memory effect" present in nickel-cadmium batteries is greatly reduced, which makes nickel-metal hydride batteries more convenient to use.

Ni-MH batteries and Ni-Cd batteries are similar in appearance, and the positive electrode of Ni-MH batteries is basically the same as that of Ni-Cd batteries, both of which use nickel hydroxide as the positive electrode, the main difference is that the negative plate of Ni-Cd batteries uses cadmium active materials, while Ni-MH batteries use high-energy hydrogen storage alloy as the negative electrode, so Ni-MH batteries have greater energy. At the same time, nickel-metal hydride batteries are basically similar to nickel-cadmium batteries in terms of electrochemical characteristics, so nickel-metal hydride batteries can completely replace nickel-cadmium batteries in use.

Nickel-cadmium battery: A nickel-cadmium battery is made up of two plates, one made of nickel and the other made of cadmium, these two metals react reversibly in the battery so that the battery can be recharged. The advantage of nickel-cadmium is that it is "strong" and cheap.

The disadvantage is that cadmium metal is polluting to the environment, the battery capacity is small, and the life is short, so the nickel-cadmium battery is the lowest-grade battery, with a memory effect, and must be discharged first every time it is charged, otherwise its memory function will greatly reduce the charging capacity of the mobile phone.

NiMH battery: NiMH battery is composed of hydrogen ions and metal nickel, with 30% more power reserve than Ni-Cd battery, lighter than Ni-Cd battery, longer service life, and no pollution to the environment, no memory effect. The disadvantage of nickel-metal hydride batteries is that nickel-cadmium batteries are much more expensive and have worse performance than lithium batteries.

The difference between nickel-cadmium batteries and nickel-metal hydride batteries is that the self-discharge rate of nickel-metal hydride batteries is much higher than that of nickel-cadmium batteries, and the energy density per unit volume of nickel-metal hydride batteries is 2 times that of nickel-cadmium batteries, and the disadvantage is that fast charging causes higher heat than nickel-cadmium batteries.

Nickel-cadmium battery is a kind of DC power supply battery, nickel-cadmium battery can be repeated for more than 500 times of charging and discharging, economical and durable. Its internal resistance is small, the internal resistance is small, it can be charged quickly, and it can provide large current for the load, and the voltage change is very small when discharging, which is a very ideal DC power supply battery.

China Battery Network.

There are detailed explanations in it.

Both have their own merits, and I will talk about them separately.

The discharge current of nickel-cadmium battery is larger than that of discharge current, and it is resistant to floating charge, and the charging voltage is highly resistant, even if the battery temperature rises, it is relatively safe and will not evaporate hydrogen.

Compared with nickel-cadmium nickel-cadmium battery, nickel-metal hydride battery does not have a memory effect, does not need to be charged after discharging photoelectricity, and has high energy density, but long-term floating charge will evaporate the hydrogen in the battery, reduce the capacity, and the withstand charging voltage is relatively narrow, and it usually needs a special charger to charge, full of self-stop. NiMH batteries will be put into the fire**.

In comparison, nickel separator batteries are relatively safe, will not be **, do not have too high requirements for charging voltage, suitable for simple equipment modification needs, mainly used in emergency lights, emergency power supply and other equipment. However, cadmium is seriously polluted, and two No. 5 nickel-cadmium batteries are put into the well, and the cadmium in the well water exceeds the standard within 50 years, which is easy to cause disease in people with weak constitution. 4 No. 5 cadmium batteries were put into one acre of cultivated land, and the food grown exceeded the cadmium standard, which was eaten by children and affected intelligence.

Nickel-metal hydride batteries do not have this problem, there is no toxicity, at this stage China does not advocate the sale and production of cadmium batteries, but because the battery has simple requirements for the charging circuit, it is still produced, and in the form of industrial packaging, a large number of emergency lights, cheap charging flashlights and other electronic equipment.

To add, if you design electrical appliances and have requirements for cost, you can use nickel separator batteries, and the charging circuit is very simple, and you can use resistor-capacitance step-down.

If you design electronic equipment and have requirements for environmental protection and battery capacity, it is recommended that you use a nickel-metal hydride battery, and add a single-chip microcomputer and a voltage regulator diode on the basis of resistor-capacitance regulator or other high-efficiency voltage regulator circuits to regulate the charge and discharge of the battery, which can improve the battery life.

If your product is not cost sensitive and does not require users to replace the battery by themselves, it is recommended that you use a lithium battery to remove the 220V transformer circuit from the appliance and be independent. The control circuit of lithium battery is mature, inexpensive, and there are many options.