Five development trends of lithium batteries for electric vehicles

If a company succeeds in disrupting electric vehicles in the future, its innovation will most likely come from the core component - batteries. The technology of the currently widely used lithium batteries has been stagnant for 10 years. If an electric car can be fully charged in 3 minutes and can take you hundreds of kilometers, it will definitely rewrite the history of transportation development.

 

In the future electric vehicle industry, new technology and good service are the conditions for car companies to dominate the market and not be eliminated! Electric balance vehicles are only more intelligent, humanized and convenient in technology. After consulting a large amount of foreign information and combining with the current well-known technical senior personnel in the industry, as one of the cores of balance vehicles: lithium batteries will show five major development trends.

Lithium-ion battery prices drop by 2/3

Pure electric cars are very expensive. The average American family is unlikely to buy a Tesla, and BYD's pure electric car E6 is not affordable for the average Chinese family. The main reason for its high cost is that the battery cost is too high.

In the past few years, driven by the national new energy industry policy, a craze for lithium battery manufacturing has swept across the country. At one time, there were more than 400 lithium battery cell and pack assembly companies (including lithium batteries for new energy vehicles), of which there were as many as 200-300 lithium battery companies involved in electric vehicles. However, behind the vigorous new energy manufacturing fever, core materials such as positive electrode material diaphragms, electrolytes, and aluminum-plastic films for soft-packed batteries are heavily dependent on imports, resulting in high cost prices for manufactured lithium batteries. The price of lithium batteries of the same capacity is more than three times that of lead-acid batteries, making market promotion difficult.

In the past three or four years, through the efforts of domestic lithium battery material companies, the core technology of manufacturing lithium batteries has made major breakthroughs. All core materials of lithium batteries used in electric vehicles have basically achieved the localization rate. At present, the price of a 48v11Ah lithium battery including a charger (using a 18650 cylindrical steel shell, each battery cell is 2200mA, and 65 batteries are connected in series and parallel) is less than 500 yuan, which is cost-effective compared with lead-acid batteries. This price is about 1/3 of the price of lithium batteries when they were first introduced to the market. It can be seen that the gradual replacement of lead-acid batteries by lithium batteries is not an empty talk.

The most expensive lithium battery at present - graphene lithium battery

Graphene is the thinnest and hardest nanomaterial known in the world, with extremely low resistivity and extremely fast electron migration. Graphene batteries are a new type of battery developed by utilizing the characteristics of lithium ions moving rapidly and in large quantities between the graphene surface and the electrode.

The world's first graphene polymer battery was developed by Graphenano of Spain and the University of Corvado. Graphenano is also the world's first company to produce graphene on an industrial scale. The energy density of common ternary lithium batteries is currently 180-200mAh/g, while the energy density of graphene polymer batteries can exceed 600mAh/g. In other words, if the battery on the Tesla P85 is replaced with a graphene battery of the same weight, its range will reach about 1,500km, three times the original.

In addition to its high energy density, graphene batteries can also be charged much faster than lithium batteries, effectively solving the problem of long charging time. They also have a long lifespan, which can be twice that of lithium batteries.

In addition, according to Graphenano, graphene batteries have superior performance, but the cost is not high, but 77% lower than lithium batteries. The use of graphene batteries will effectively reduce the cost of electric vehicles and thus enhance market competitiveness.

Wireless charging technology has a broad market

Compared with traditional charging stations and charging piles, wireless charging has the following main features: flexible layout of charging facilities. Electric vehicles can be charged by simply renovating existing parking lots and roadside parking spaces, and even the transmitter can be buried under part of the road surface. At that time, electric vehicles can be charged while driving on these roads, which will not occupy too much urban space; it is more convenient for users to use. High-speed wireless charging can be achieved without plug-in cables, which not only eliminates the parking and waiting time required for traditional charging pile wiring, but also extends the charging lanes that have appeared from static wireless charging to dynamic wireless charging, greatly reducing the user's fixed-position charging time and increasing the utilization rate of electric vehicles. For example, the receiving boards on both sides of the Formula E track can charge electric racing cars at the moment they are speeding past; the charging process is relatively safe. Wireless charging has no sparks or electric shock hazards, no dust accumulation and contact loss, and can adapt to a variety of harsh environments and weather.

It is reported that many companies are now beginning to research wireless charging technology for electric vehicles. In January this year, ZTE and State Grid announced the establishment of a joint venture in Chengdu to provide wireless charging services for electric vehicles. After that, ZTE and Dongfeng Motor built China's first public bus wireless charging demonstration line.

Battery Management System (BMS)

As the energy source of the entire balancing vehicle, the battery is the focus of safety protection. For electric vehicles, battery explosions and battery failures are common. As the power system of electric vehicles becomes increasingly complex, the functions that the BMS needs to perform increase, and the burden it bears is unprecedented. An excellent and intelligent BMS solution can not only extend the service life of the battery, but also has the potential to extend the driving distance of the car in pure electric drive mode.

Taking i-ROBOT's battery management system as an example, i-ROBOT's BMS can fully intelligently adjust and charge the vehicle body. At the same time, it uses online repair technology to strengthen the battery's 24-hour uninterrupted maintenance, truly increasing the battery's service life by more than 50%:

● The most advanced imported high-rate (maximum 10C discharge) power cells

● Monitoring of battery voltage and current signals, and detection of battery pack temperature

● High-precision SOC estimation

● Multiple safety protection mechanisms: complete control of charging and discharging for short circuit, overcurrent, overvoltage and overheating.

● Wide operating temperature range of -10℃~45℃

Modular battery technology stacks batteries like building blocks

The new Macbook uses modular battery technology. Apple engineers designed a stepped battery grid and stacked several layers of batteries, which can increase the power of Apple products by 35%.

Now this technology has also gained followers in the field of self-balancing vehicles. The latest igo mobility robot launched by i-ROBOT (Shanghai New Century Robot Co., Ltd.) adopts a modular lithium-ion battery system, which greatly improves the battery capacity and facilitates capacity expansion.

The modular battery system consists of a flat battery assembly consisting of battery cells, which can be combined into different sizes and performances according to people's needs. Battery modular technology, or more precisely, flat battery assemblies can have different battery capacities, voltages and sizes according to needs. The number and length of battery cells in each flat battery assembly can be different.

The modularity of battery design may create a new, interactive battery model that can be used in both cars and home life without the need for redesign and reassembly.

Perhaps we are witnesses of an era in which energy is once again being replaced, and the future large batteries that will provide us with energy are the result of continuous upgrades from the original inconspicuous small batteries.

The battery is the core component of electric vehicles, which directly determines the most critical range of electric vehicles. As new energy gradually heats up, the investment in the battery industry is also increasing. In the next few years, battery technology will usher in rapid development, and balance bikes, as the "smart pioneer" of electric vehicles, will also benefit greatly from it.