Digital battery

As the core of electric vehicles, power battery applications with the particularity and complexity. To say, have the last hundred years, not the power battery development is bad, but the oil industry and the automotive industry is too large outstanding technological progress. Power Battery experience in the manufacture of batteries, batteries, battery modules, batteries, four-level links, the whole power system, Laptop battery technology has repeatedly stressed the concept of necessity is: consistency, standardization steps. From a technical achievement levels, ranging from small battery-battery technology upgrade to power, not simply “addition” can be easily reached. Power Battery performance factors (power density, energy density, durability, safety, cost) rings linked, high-power and high energy prices on the development and manufacture of hard to take into account a long time a serious impact on the work of the high-power battery, High-Power exothermic phenomenon of the work of the security of the test battery, energy efficiency must be sacrificed in order to obtain a longer life, high energy density and safety risks. This is technically difficult to obtain a full range of meeting, but only to find a balance, but also with the vehicle fuel system that is the biggest challenge for technology comparison. Route choice in technology, nickel metal hydride batteries, native defects (self-discharge, specific energy is small), it was replaced by lithium batteries, only a matter of time. However, the lithium battery line, a series of disputes can the electrode materials, different systems of lithium manganese oxide have, lithium iron phosphate, nickel-and cobalt-manganese ternary and other technical line. Of the lithium iron phosphate battery technology A123Systems lost Chevrolet tender incidents, automobile manufacturers program the freedom of choice of batteries, for a variety of technical path to wait. We believe that automobile manufacturers’ lithium IBM ThinkPad R40 battery technology is not just over the line, more concerned about the patent dispute, suppliers, manufacturing capabilities and financial strength, etc., it is systemic issues. Main lithium-ion battery makers are still the most commonly used lithium manganese oxide system, Ni-Co-Mn and other technical way, as we believe that given the uncertainty in technological progress, lithium battery technology fronts will be difficult in the 2-3 years will have a clear statement does not preclude the international community, the first benefit of industrialization is the more mature xHEV lithium manganese, nickel, cobalt and other battery-Mn line. Battery is still in the global industrial R & D phase is uncertain, the domestic industry structure and outlook, it is certain that China is in the technical research and development of battery power, battery and vehicle research and development and improve the docking Power battery industry support intensity.

 

The direction of the battery lithium ion battery that can be in Japan and the United States of lithium-manganese-lithium-divided iron. Lithium manganese battery refers to the lithium manganese oxide cathode materials LiMn2O4 in propulsion. Lithium-iron Dell Latitude D510 battery refers to the lithium iron phosphate as cathode material LiFePO4 Power Battery. Us for a comparison:

 

Security

 

Lithium-ion battery charging and discharging process of lithium-ion embedding / de-embedding process. When the crystal structure in the process stability, not change is the battery of security to be high. Otherwise, is that is small, such as the layered structure of the cobalt oxide lithium battery charging voltage rises under the circumstances, the cathode material of lithium ion in the other continued to de-embedded to swim with the cathode, anode material at a time when the filled in the position to the location of the lithium-ion site was, lithium-ion only in the form of metal precipitation on the surface. Such problems arise. On the one hand, the surface of lithium metal deposition is very simple, formed a branch of the form, poly-lithium dendrites, the membrane-penetrating, leading to positive and negative direct short circuit, the other hand, lithium metal is very lively, is a direct response to the electrolyte and heat have, at the same time, the backup lithium is very low, although it is not the surface of the lithium metal dendrite membrane-penetrating, as long as the temperature is slightly higher, as the hp Pavilion DV1000 battery by heating by the discharge of lithium is -melt metal, so that positive and negative short-circuit, causing accidents. There is a high temperature and depth of the charge-discharge process, the cobalt and oxygen bond can be broken to release oxygen and produce an explosion. Lithium cobalt oxide battery temperature of only 150 degrees, the lowest of the three cathode materials. Therefore, the security of the largest lithium cobalt oxide is a short-board batteries.

 

Lithium manganese spinel crystal battery, lithium-ion embedding / de-embedding process is stable, secure high. The oxidation temperature of 250 degrees of lithium cobalt oxide batteries than a full 100 degrees higher. However, in the depths of the charging and discharging the material lattice Kawasaki (susceptible to changes, especially at the higher temperature), and manganese-oxygen bond can be broken to produce and release oxygen in an explosion. There is also a high temperature lithium-manganese oxide crystals slowly dissolved in the electrolyte problems. Lithium manganese battery and must therefore take a variety of security measures to improve security.

 

Lithium iron phosphate sony VGP-BPS2A battery is currently the safest battery. Its unique crystal structure of olivine in the phosphate-base for the entire material has a stabilizing effect, makes the material itself has thermal stability and good cycling performance. This is one of the key in the lithium iron phosphate lithium-ion differs from LiCoO2 cathode material of lithium cobalt oxide and lithium manganese LiMn2O4 with a one-dimensional direction of their mobility, the charge-discharge process can undo and be accompanied by extrusion, and move a central metallic iron oxidation and reduction. In addition, the phosphorus-oxygen bond and strong, so lithium batteries short-circuited, it is not because of the short circuit and produce an explosion. The oxidation temperature is higher than 400 degrees, can be placed on the fire. Therefore, increasing the cathode material lithium cobalt oxide and manganese-lithium battery for the safety had to take on a variety of means, while the cathode material lithium iron phosphate is a naturally have security.

 

Economy

 

How much do the cobalt to the high price of lithium cobalt oxide material. Manganese is rich in natural resources are cheap, while lighter lithium manganese preparation, manganese-lithium batteries and low cost. Phosphorus and iron-rich cheap, but difficult to lithium iron phosphate preparation for its low rate of sintering of the finished product, so that the material lithium iron phosphate battery costs. To reduce the cost of lithium iron phosphate a variety of methods, such as increased production, improved technology and so on.

 

High Capacity

 

Including the electrical power and voltage. Theory of the highest capacity in the lithium-cobalt, manganese and lithium the lowest. However, in order to assess the safety, the actual performance of lithium cobalt oxide of a compromise, only about half the theoretical capacity. Thing like this would, if you have to increase generating capacity to sacrifice safety. Security, high theoretical lithium manganese oxide with a low capacity means that there is not much scope for the development of electric power and up to 148mAh / g VGP-BPS10 with greater safety in comparison, lithium iron phosphate, it was made in the laboratory 160 mAh / g capacity of the actual performance. Of course, the operating voltage of lithium iron phosphate as low as 3.3. But it has a very flat voltage platform, which means it is more stable and efficient discharge properties.

 

Fast Charge

 

Speed of charge from the conductive material decision. There is no doubt the worst of lithium iron phosphate. This is because the lithium iron phosphate lithium-ion extrusion, reducing the volume of the grid, from which a total FeO6 octahedron corners, because they can not be separated by oxygen atoms to form a permanent FeO6 network structure, whereby the electronic conductivity. On the other side of the crystal in the oxygen atom near the main road of tightly packed six-party agreement, so that the lithium-ion offers only limited access, allowing lithium ions in the structure at room temperature in a very small migration rates. But that does not mean that lithium manganese oxide can be easily achieved fast loading. Because of its crystal structure of lithium iron phosphate is not stable, high current fast charge may mean that the bars come saki changes, the key of the manganese and oxygen can be broken, which means an explosion. By pair-doped lithium iron phosphate, for example, by adding carbon, cobalt and the like will be the conductivity is greatly increased. BYD experiments reported that his 10 minutes to the apple M8403 battery to 80% are filled.

Come on, the first single-crystal silicon solar batteries. Silicon is very abundant on earth, an element almost everywhere, the presence of silicon can be said to be inexhaustible, make using silicon solar batteries, in fact, no shortage of raw materials. However, refining, it is not easy, so people in the production of monocrystalline silicon solar batteries at the same time she studied the polycrystalline silicon solar batteries and solar batteries made from amorphous silicon, has commercial-scale production of solar batteries, not directly from a series of silicon . In fact, semiconductor materials for the production of solar batteries, a site with the materials, industrial development, solar batteries are more varieties. Has the research and development of solar batteries, in addition to the silicon series, there is cadmium sulfide, gallium arsenide, copper indium selenium, and performed many other types of solar batteries is endless, the following describes some of the most common solar Laptop battery .

 

Monocrystalline silicon solar batteries

 

Monocrystalline silicon solar batteries is currently the fastest developing a solar battery, has completed its process of composition and production, the product was to be widely used in space and ground facilities. These high purity single-crystal silicon solar batteries with rod as raw materials, 99.999% purity requirements. To reduce production costs, and now solar-terrestrial applications such as solar-grade silicon rods, material increases performance index. Some semiconductor devices can also be used to end the processing of waste materials and sub-end silicon materials, through re-pull rods of single crystal silicon solar VGP-BPS2C batteries made battery-specific. Slice the silicon rods, typically 0.3 mm thick films. Wafer after forming, polishing, cleaning and other processes that are processed from silicon raw material. The processing of solar film, we must first-doped silicon and the distribution, generally as a small amount of dopant boron, phosphorus, antimony and others. Distribution in the quartz in the high-temperature diffusion furnace checked. This has formed on the silicon P / FONT> N-junction. And then, with screen-printed, will be printed with a good paste of silicon gate line out, made after sintering at the same time back electrode and the gate lines in an area source of anti-reflective coating on a large number of photons prevent smooth silicon surface reflection path, now, single-chip silicon solar batteries are produced. Single-Chip through the random testing in accordance with the prescribed specifications) in a solar components (solar batteries, with serial and parallel processes are linked together to form a certain degree of output voltage and current, the final framework for packaging and packaging materials. Users on system design, can have a variety of solar components in various sizes of solar phalanx, also known as solar arrays. Monocrystalline silicon solar VGP-BPS9/B batteries currently photoelectric efficiency of around 15%, laboratory results were more than 20%. For the space station by up to 50% of the solar batteries.

 

Polycrystalline silicon solar batteries

 

Monocrystalline silicon solar battery production requires enormous amounts of high-purity silicon material, while the production of these materials, complex process, energy consumption and large, is the total production of solar batteries super-half, with a combined single-crystal silicon rod was drawn cylindrical, cut wafer-production of solar batteries is to form a flat-utilization of solar energy components. Therefore, the 80 years since the state has put in some European and American development of polycrystalline silicon solar batteries. Currently, the use of polysilicon solar hp PB991A battery materials depends, above all, a collection of a large number of single-crystal particles in it, or melt from wastes time monocrystalline silicon materials and metallurgical grade silicon material made votes. The process is to select resistance of 100 ~ 300 ohm-cm block of material or polycrystalline silicon material by squeezing the end with a 1:5 mixture of hydrofluoric acid and nitric acid corrosion, and then spent the end of the appropriate neutral-ionized water rinse and dry. Quartz crucible loaded with a good polysilicon materials, which can be the addition of boron-silicon amount, the casting furnace, the heating and melting in a vacuum. After melting insulation around 20 minutes, and then injected into the graphite form, which is solidified during slow cooling, the polysilicon can ingots. This cube can be made of silicon ingots to be processed into square slices solar film, can improve recycling and to facilitate the installation. Polycrystalline silicon solar batteries with single-crystal silicon solar Dell Latitude D510 battery manufacturing process is similar to the photoelectric efficiency of about 12%, somewhat lower than single-crystal silicon solar batteries, but the material is simple, the power consumption of the total production costs are low, save as to obtain a significant development . As the technology has improved, the current efficiency of polycrystalline silicon to reach around 14%.

 

Amorphous silicon solar batteries

 

Amorphous silicon solar batteries in 1976 appeared a new thin-film solar batteries, monocrystalline and multicrystalline silicon-silicon solar batteries with the production of an entirely different way silicon low material consumption, low power consumption, very attractive. Production of amorphous silicon solar batteries There are several possibilities, the most common is the glow discharge method and reactive sputtering, chemical vapor deposition, electron beam evaporation method and thermal decomposition of silane-law. Glow discharge method is a quartz container in the vacuum pump, filled into the hydrogen or argon diluted silane, with the RF power supply heat, so that silane ionization, the formation of plasma. Amorphous silicon films deposited on the heated substrate. If the silane in the right amount of hydrogenated phosphorus or boron hydride were mixed, can be obtained from N, or P-type amorphous silicon layer. Substrate general use glass or stainless steel. Production of amorphous silicon thin-film process, which mainly depends on the strict control of pressure, flow rate and RF power on the substrate temperature is also important. Amorphous silicon solar batteries have altered structures, which is a better structure called PiN IBM ThinkPad R52 battery, the substrate of the earliest sedimentary layer of the N-type phosphorus-doped amorphous silicon is deposited, and then a layer of undoped i-layer is deposited and then A layer of boron-doped p-type amorphous silicon, and finally a layer of electron beam evaporation of anti-reflective coating, and evaporation of silver electrode. This production, a series of deposition chamber can be used in production to provide a continuous process to achieve mass production. At the same time, a very thin amorphous silicon solar batteries of the composite type can, or use in the manufacture of integrated circuits, obtained in a plane with the corresponding mask process, a number of the serial production of battery to a higher voltage to be . For the general single-crystal silicon solar battery voltage of 0.5 volts or so, and now the Japanese production of amorphous silicon solar batteries in series of up to 2.4 volts. The current problem is that amorphous silicon solar battery efficiency is low, the international advanced level of about 10%, and is not stable enough, and often fall down conversion efficiency of the phenomenon that we are not yet widely used in the manufacture of large solar installations, and get into the low-light power supply, bag, such as electronic calculators, electronic watches and clocks, and copier and so on. Estimation of the efficiency decrease to overcome the problem, the amorphous silicon solar BATBL50L6 batteries will promote the great development of solar energy, because it is inexpensive, light weight, the application is convenient, it can be combined with the housing of the roof of an independent power households.

 

 

Multi-compound solar batteries

 

Multi-compound solar batteries that not a single item from semiconductor materials, solar batteries. Today, there are a variety of research, although most industrial production have not yet, but indicates that photoelectric conversion of the beauties of spring. Now a few brief introduction:

 

(1) CdS solar batteries - as early as 1954, Reynolds has discovered CdS photovoltaic effect. In the year 1960 was the rule of law vacuum evaporation of CdS solar batteries, photoelectric efficiency of 3.5%. By 1964, the United States of cadmium sulfide solar batteries, photoelectric efficiency increased to 4% ~ 6%. Later, lays down in Europe from a flood of CdS solar battery development, the photoelectric efficiency of up to 9%, but still can not compete with the polycrystalline silicon solar batteries. But people never give up, in addition to the massive study of sintered CdS solar apple A1175 battery, but more emphasis on research-type CdS thin-film solar batteries. It is as a barrier layer of cuprous oxide to hydrogen sulfide heterojunction CdS materials used form, according to theoretical calculations, the photoelectric efficiency of up to 16.4%. Chinese Academy of Sciences, Changchun Institute of Applied Chemistry in the early 80s once made to achieve CdS thin-film photoelectric efficiency of solar batteries to 7.6% respectively. Previously, some countries have continued to look at the development of cadmium sulfide solar batteries, to solve, because it is simply a relatively simple fabrication, equipment problems.

 

(2), gallium arsenide solar batteries - gallium arsenide solar batteries, a very good material, it is better suited to approximate the solar spectrum and can produce high temperatures at 250 ℃ under the terms of the photoelectric conversion resist performance is still good, sensors offer the highest efficiency of about 30%, particularly suitable for high temperature solar concentrators. Series of solar batteries has been studied with single-crystal gallium arsenide GaAs, based polycrystalline gallium arsenide, aluminum gallium arsenide - gallium arsenide heterostructures, metal - gallium arsenide semiconductor, metal - insulator - semiconductor gallium-arsenic solar VGP-BPS13 batteries and so on. GaAs material preparation of semiconductor materials like silicon, there is crystal growth method, the direct method generated, vapor growth method, liquid phase epitaxy method. For more scarce because of gallium, arsenic, toxic, manufacturing costs are high, affecting the development of such solar batteries.

 

(3), copper-indium-selenium solar batteries - copper, indium, selenium, and ternary compound semiconductors as a starting material of the solar battery. It is a polycrystalline thin film structure to use, and typically vacuum coating, electrically, electrophoresis, etc. or chemical vapor deposition process for the preparation, less material consumption, low cost, stable performance, photoelectric efficiency of over 10%. Therefore, an amorphous silicon thin film solar batteries can compete with the new type of solar batteries. Added Recently developed thin-film copper-indium-selenium, to the amorphous silicon thin film laminated on a solar battery can improve the efficiency of solar batteries and the efficiency of amorphous silicon photovoltaic overcome decline below.

 

Currently we are using are basically on polysilicon and monocrystalline solar batteries concentrate.

Battery power supply design is the development of chemicals and the workers of scientific research, technical staff, knowledge and skills.

 

1. Battery Design Basis

 

• The design goals of battery and the basic principles of

 

Cell is the design of instruments and equipment to provide the best use of the performance of work or power outlet. Therefore, the design of the Laptop battery must first be used to meet the electrical requirements and optimize it with the best overall performance, to determine the battery electrode, electrolyte membrane, Shell and other parties parameters, and they are hand are made to specifications and indicators of battery or batteries.  

  

• design of the battery requirements

 

Battery is designed to meet the object (or user equipment) made the request. Therefore, when designing the battery, the first to have a detailed understanding of the items on the performance indicators of the battery conditions and user requirements, generally include the following:

 

• the battery voltage;

• Battery operating current is the normal current and peak current;

• Battery working hours, including time to discharge continues, the use of the term or life cycle;

• Battery work environment, including hours of work in which the Dell Latitude D510 battery status and temperature;

• The maximum size of the battery.

 

Should also be taken into consideration: the source material; battery performance, characteristics of the battery of the determinants of battery technology, economic indicators, environmental issues and other factors.

 

• performance assessment battery of key indicators

 

Battery performance in general, mainly the following aspects to evaluate.

 

(1) The capacity of the battery capacity is defined as a rejection of certain conditions, can be obtained from the battery power, which is currently on full time, generally expressed in Ah or mAh, this which directly affects the maximum operating current of the hp Pavilion dv4 battery and working hours.

 

(2) The discharge characteristics and internal resistance characteristics of battery discharge is granted the discharge of the battery in a system, the fineness of its operating voltage, the voltage level of the platform and the performance mainstream discharge, etc., which indicates that the battery with a capacity load. Battery internal resistance including the ohmic resistance and polarization resistance electrochemical discharge current large, the resistance of the flow characteristics are particularly evident.

 

(3) Operating temperature with electrical work environment and conditions require the use of batteries in a specific temperature range with good performance.

 

(4) The storage performance of the storage sony VGP-BPS5 battery for a while because of certain factors for changes in performance, causing the battery to discharge, leakage of electrolyte, the battery short-circuit and so on.

 

(5) life cycle (secondary battery) life cycle means the system of secondary batteries in accordance with a certain load and discharge its functions reduced to a certain level (for example, the initial capacity of 60% ) when the number of cycles.

 

(6) The internal pressure and resistance performance overload (secondary battery) for Ni-Cd, Ni-MH battery and other sealed type secondary, high current for recharging the battery internal pressure can reach the balance and equilibrium pressure of the high and low resistance of the battery current level of overcharging to measure the performance of performance are all important indicators of good or bad, if the battery internal pressure reaches the equilibrium or balance, the pressure is too high, it will limit the devices battery voltage (such as explosions bullet proof) to open the battery caused by discouragement or neglect fluid, which leads rapidly to the failure of the battery. If the device fails, pressure limiting, there may cause cracking of the tank apple iBook G4 14 inch battery or an explosion.

 

2. Battery design the basic steps

 

Battery design staff in design tasks clearly and fully prepared, you can imagine.

 

User requirements depending on battery design ideas from the battery, there are two: one for electrical equipment and instruments, rated capacity of the power source, and another is just one factor given power supply form developed excellent battery performance specifications for new or special-shaped battery.

 

1 to determine the ability of design steps of the battery

 

• determine the number of combined organ cells Tenor battery voltage of single battery and current density.

• According to user requirements to determine the overall work of the battery voltage, current indicators of operating and other series of selected cells, the light of the series “Volt-Ampere curve “(derived from empirical data or experience) to determine the work voltage of single cell and current density.

• determine the number of batteries in a single cell.

= The number of total voltage single battery voltage / battery

• Calculation of battery capacity

• According to the requirements of course work and working time calculations of charge.

Nominal Capacity * = current operating hours

• determine the design capacity of

Design capacity = capacity * Design factor

A design factor is to ensure the reliability and lifetime of the whole of the battery, the general attitude 1.1-1.2