What does a car battery box do?

Battery box is a box dedicated to storing batteries: a SLR camera handle has a battery box, a camera has a battery box, and so on.

SLR camera battery box, the role is usually three points:

1, the first is to expand the number of batteries, increase the camera use time;

2, followed by the addition of vertical shutter and the main dial, AF-ON button, etc., for easy operation;

3, in addition, after adding the handle, the weight center of the fuselage is shifted backwards, and the height of the camera is increased to extend the balance arm held by the hand, so that the stability and balance of the camera equipped with a telephoto lens will increase, making it easier to shoot in hand.

It is a device that converts chemical energy into electrical energy and belongs to a DC power supply. Its role is:

(1) When starting the engine, provide a strong starting current (about 10A) to the starter.

(2) When the generator is overloaded, it can assist the generator to supply power to the electric equipment.

(3) Power to electrical equipment when the engine is idle.

(4) The battery is also a large-capacity capacitor that can protect the car's electrical appliances.

(5) When the voltage at the end of the generator is higher than the electromotive force of the lead battery, part of the electrical energy is converted into chemical energy and stored, that is, charging.

Electric vehicle batteries are the source of power on electric vehicles. Nowadays, the vast majority of electric vehicles are equipped with lead-acid batteries. The lead-acid batteries have low cost and high cost. Because this battery can be recharged and can be used repeatedly, it is called a "lead-acid battery."

In 1860, France's Plante invented a battery using lead as an electrode, which is the precursor of a lead-acid battery.

The following four power batteries can be used by electric bicycles, namely valve controlled lead-acid free maintenance batteries, colloidal lead-acid batteries, nickel-metal hydride batteries and lithium-ion batteries.

Lead acid batteries

Lead batteries are widely used and widely studied by various electric vehicles in various countries because of their low price, rich material sources, higher specific power, mature technology and manufacturing process, and high resource recovery rate. Electric bicycle has been widely accepted as a personal means of transportation that saves energy, convenience, speed, comfort, cheap and zero emissions, and has received the attention of the relevant departments of the country. The "Strategic Research on the Development of the Light Electric Vehicle Industry" task group, which was participated by the Development Research Center of the State Council, the National Development and Reform Commission, the Ministry of Construction, and the Ministry of Science and Technology, submitted the "Strategic Research on the Development of the Light Electric Vehicle Industry" report. The number of electric bicycles in the country has reached more than 30 million. More than 95% of electric bicycles use VRLA batteries. [ 1]

The vast majority of commercial electric bicycles are sealed lead-acid batteries, which do not need to be replenished frequently and are maintenance-free. The main chemical reaction is: PbO2+2H2SO4+Pb←Charging, Discharging→2PbSO4+2H2O

When the lead-acid battery is charged, the cavernous lead at the yin and Yang poles that become lead sulfate releases the sulfuric acid components that are fixed therein into the electrolyte, which becomes cavernous lead and lead oxide, respectively, and the concentration of sulfuric acid in the electrolyte continues to increase.; On the contrary, the lead oxide in the anode and the sponge lead on the cathode plate react with the sulfuric acid in the electrolyte to become lead sulfate, and the concentration of sulfuric acid in the electrolyte continues to decrease. When the lead-acid battery is undercharged, lead sulfate of the yin and Yang bipolar plate can not be completely converted into cavernous lead and lead oxide. If the long-term charging is insufficient, lead sulfate crystals will result in vulcanization of the polar plate and poor battery quality. Conversely, if the battery is over-charged, the amount of oxygen produced by the anode is greater than the adsorption capacity of the cathode, so that the internal pressure of the battery increases, resulting in gas spillage, electrolyte reduction, and may also cause the active substance to soften or fall off, and the battery life is greatly shortened.

The comprehensive performance has been greatly improved

In the past 10 years, the comprehensive performance of Valve controlled lead batteries for electric bicycles has been greatly improved. Take the 6-DZM-10 battery as an example. In 1997, there was insufficient capacity in this type of battery, and the discharge capacity of 2H rate(5A) was less than 10Ah; Low specific energy, 2 H rate specific energy is less than 30 W/kg; The life is short, and the cycle life of 100 % discharge depth is only 50 to 60 times(before the capacity drops to 8Ah; The following is the same), the service life is only 3 to 5 months and other issues.

By 2003, the 2h rate (5A) discharge capacity reached 11~13Ah; the 2h rate specific energy reached 33~36Wh/kg; the 100% discharge depth cycle life reached 250~300 times, and the service life could reach more than 12 months. The problems with valve-regulated lead-acid batteries for electric bicycles have basically been solved.

There is a new breakthrough in the deep cycle life performance of this type of battery. The main performance is: 2 H rate(5A) discharge initial capacity of 14 Ah; The 2H ratio reaches 38 Wh / kg in energy; The cycle life of 100 % discharge depth exceeds 400 times, and the total discharge capacity is 4500 Ah, corresponding to the accumulated mileage of about 18,000 km(in 4km/h, the same below). The maximum deep cycle life is more than 600 times, and the total release capacity is 6151 Ah, and the corresponding cumulative mileage is about 24600 km. If the capacity is less than 7Ah as the end of life sign, the deep cycle life is 943 cycles, the total release capacity is 8710Ah, and the corresponding accumulated mileage is about 34,800 km. If a battery with a total capacity of 2250 Ah and a corresponding cumulative mileage of 9,000 km is released with a deep cycle life of 250 times or a total capacity of 2250 Ah, it can be guaranteed to be used for 1 year. [ 1]

Pay attention to matching with charger

In many years of use practice, electric bicycle manufacturers and battery manufacturers have gradually realized the importance of matching between battery and electric drive system related equipment, especially with chargers. Manufacturing quality is the premise of battery quality, but only when used together with its matching charger can the high quality battery should have superior performance, otherwise the high quality battery can not fully play its potential superior performance. [ 1]

Due to the difference in formula, structure, acid concentration and so on, the suitable charging parameters of different batteries are different. For example, in our study, we found that the charging parameters of different batteries during the constant pressure phase can vary by 1.5 to 2.0 V (for 36 V batteries). The basic requirement for suitable charging parameters is to ensure that the battery can be filled without abnormal attenuation of the battery capacity due to under-charging; Make sure that the battery does not lose water and heat during the life of the battery due to overcharging. [ 1]

Lead batteries for pure electric vehicles

The open-type lead batteries used in early pure electric vehicles have adopted the results of the "August 5th" planning period and have achieved successful experience of 19 months (120,000 kilometers). The key is to accumulate a system to control the charging method, discharge depth, timely water supply, such as a set of work experience and careful maintenance experience. In recent years, four-wheel micro-electric vehicles (including tour buses, patrol cars, golf carts, short distance road vehicles, etc.) have developed rapidly. Most of the vehicles used in the car are open lead batteries. The corresponding type of battery is favored by battery manufacturers. [ 1]

The electric vehicle adopts a valve controlled sealed lead battery new product, its performance is: 3h rate capacity 55Ah; The specific energy at the 3h rate is 33 Wh / kg and 84 Wh / L; The cycle life of 75 % of the discharge depth reaches more than 400 times. It is believed that the successful experience of Valve control lead battery for electric bicycle can be extended to pure electric vehicle valve control lead battery, and the performance will be further improved. [ 1]

Lead batteries for hybrid electric vehicles

Hybrid electric vehicles are now divided into three categories: lightly hybrid (ie, electric systems are mainly used to start and recover braking energy, 42V electric systems that will be promoted in all cars belong to this type), moderately mixed (ie electric) The system is used to start, recover braking energy and medium and short distance travel), heavy hybrid (ie electric system for starting, recovering braking energy and driving over longer distances, also known as "Plug-in"). [ 1]

It has been clearly stated in the literature at home and abroad that in light hybrid electric vehicles, Valve controlled lead batteries have advantages, mainly because of their low cost, mature technology, and reliable performance; Valve controlled lead batteries for moderately mixed electric vehicles, ALABC(Advanced Lead Acid Battery Consortium) is being organized to compete with MH-Ni batteries for the market for moderately mixed electric vehicles, Wrap bipolar batteries and TMF(metal film) batteries have been introduced and tested in vehicles; In the field of heavy hybrid electric vehicles, the lead battery has low specific energy and can not meet the requirements of the long distance driving of the electric system. [ 1]

Colloidal battery

It is an improvement on ordinary lead-acid batteries for liquid electrolytes. It uses gelatinous electrolytes, and there is no free liquid inside. At the same volume, the electrolyte has a large capacity, a large thermal capacity, and a strong thermal dissipation ability, which can avoid the thermal runaway phenomenon that is easily generated by general batteries. The electrolyte concentration is low and the corrosion to the plate is weak; The concentration is uniform and there is no acid layer phenomenon.

Nickel hydride battery (Ni-MH)

Nickel-metal hydrogen batteries are the rookie of the battery family that emerged in the 1990s and have developed rapidly. The electrode reaction of the Ni-MH battery is:

Positive: Ni(OH)2+OH-=NiOOH+H2O+e-

Negative: M+H2O+e=MHab+OH-Ni(OH)2+M=NiOOH+MHab

It is an alkaline battery with a nickel-cadmium battery. It only replaces the negative material cadmium CD and electromotive force of the nickel-cadmium battery with an alloy material (MH) that absorbs hydrogen. It has all the superior properties of a nickel-cadmium battery, and its energy density is higher than that of a nickel-cadmium battery. The main advantages are: higher than energy(the distance that can be exercised for a single charge); High specific power, can also discharge smoothly when working in high current(acceleration climbing ability is good); Low temperature discharge performance is good; Long cycle life; Safe and reliable, free from maintenance; No memory effect; There is no pollution problem to the environment, and renewable use is in line with the concept of sustainable development. However, Ni-MH batteries are too expensive and expensive.

Lithium-ion batteries

Lithium-ion batteries were first introduced to the market by Sony Corporation in 1990. Its advantage is that it is higher than energy and is currently the highest than energy battery. It has been widely used in portable information products.

Lithium-ion batteries are generally considered to have the following advantages: larger than energy; Higher than power; Self-discharge is small; No memory effect; Good cycling characteristics; Can discharge rapidly, and high efficiency; Wide range of operating temperatures; There is no environmental pollution, so it is expected to enter the ranks of the best power supply in the 21st century. It is expected that the market share of MH/Ni batteries will shrink during the period 2006-2012 when lithium ion batteries are further developed. Lithium-ion market share will expand. There are already electric bicycle products that use lithium ion batteries for sale.

Driven by the development of a new type of cheap cathode material with good safety, good recycling performance, and high capacity, the lithium ion battery used in electric bicycles is nearly practical. There are several more mature lithium-ion batteries for electric bicycles equipped with battery management systems (BMS). There are also electric bicycle manufacturers that specialize in the production of lithium ion batteries. The author thinks that the lithium ion battery used in electric bicycle will be the first power battery used in the car in large quantities. It will be a large proportion of practical batteries after lead batteries, and will also become a battery for high-end electric bicycle products. There have been many reports on the demonstration of large lithium-ion batteries in pure electric cars and electric buses, as well as on hybrid electric vehicles. According to the current level of development and experience of lithium-ion batteries, the safety of batteries under 48V10Ah for electric bicycles is guaranteed, but large lithium-ion batteries need to do a lot of hard work for commercial electric vehicles. The main reasons for this are: pure electric cars and electric buses, as well as the number of batteries used in hybrid electric vehicles, the complexity of the system, the greater difficulty of safety, the higher requirements for reliability and consistency, and the high price. It has been reported that Shenzhen BYD will provide 200 electric cars powered by lithium-ion batteries in 2005 to form a taxi fleet. It has now been postponed until 2007. [ 1]

Fuel cell

The fuel cell directly converts chemical energy into electrical energy to supply the motor to drive the vehicle. Its main advantages are: high efficiency, fuel saving; zero emissions; low noise, etc., especially suitable for vehicle power source. Hydrogen fuel cell vehicles will be ideal for replacing cars that are fueled by petroleum products. [ 1]

Zinc-nickel battery (Zn-Ni)

The Zn-Ni battery was once considered to be an electric vehicle battery that should be promoted. Judging from the market screening of 4 to 5 years, there is almost no use on commercial electric vehicles. This is mainly due to the high price of Zn-Ni batteries (2.5 to 4 yuan per VAh, 4 to 6 times that of lead batteries); During the cycle process, the initial capacity attenuation rate is large, which affects the actual useful life of the battery pack. In addition, the rapid development and lower price of lithium-ion batteries make Zn-Ni batteries less competitive in electric vehicles. [ 1]

Zinc air battery

Zinc empty battery is a kind of metal-air cell and belongs to the category of semi-fuel cell. It has the advantages of higher energy, rich raw materials, low price, and no pollution. It is considered to be a competitive candidate for electric vehicle batteries.

Chinese-Americans established PowerZincc, which produces machinery that can be filled with zinc empty batteries, in Shanghai and has built a demonstration workshop. The electric bicycles and electric motorcycles were equipped with zinc empty batteries to carry out mileage tests, reaching 150km and 250km, respectively, and did a lot of promotion and application work. 50 battery replacement points were established in Shanghai. However, less than 1 year, this promotion trial work stopped, and the result of the market screening was not accepted by the user. Since then, with the support of some leaders, an electric bus powered by the manufactured zinc empty battery has been built. However, due to the low power performance of zinc empty batteries, the start-up and acceleration performance of the car is obviously poor. A lot of work has been done at home and abroad in developing zinc empty batteries for electric vehicles. In recent years, the research and development of zinc empty batteries for electric vehicles has re-emerged. However, the practice has confirmed the advantages of zinc empty batteries. At the same time, it has also exposed some problems that have been reported abroad, such as zinc electrode replacement service systems and regeneration costs. The life of oxygen electrodes, Electrolytic fluid leaks, crawls or spills from batteries.

The page contains the contents of the machine translation.