The technological roadmap of new energy vehicles in China has undergone a long period of evolution,Transition strategy from energy-saving and new energy vehicles to pure electric drive technology,Moving on to the strategy of building a strong country in the field of new energy vehicles. Today, we will look at the future development from a technical perspective.
Prospects of Pure Electric Power Technology
self2008Lithium ion power batteries have been applied to electric vehicles in the year10year,The energy density of actual loaded products has increased2.5times,We have achieved a revolutionary breakthrough in the field of batteries over the past century.2020Our goal for the year is300watt-hour/kilogram,This is a common goal,And China is also fully prepared.
From a vehicle perspective,What matters is the volumetric energy density, not the weight energy density,Lithium ion batteries have advantages in this regard. Current lithium sulfur batteries and lithium air batteries,Although the theoretical weight and energy density are relatively high,However, the volumetric energy density is currently difficult to surpass that of lithium-ion batteries.
In this regard,We believe that lithium-ion batteries have the potential and prospects to become the mainstream technology for power batteries,But the bottleneck of development is the safety of high specific energy power batteries.2018There were some safety accidents in the year,The batteries used in these accident vehicles are basically2016Produced around the year,probablyNCM523System. With the application of high nickel,The thermal stability of the battery will deteriorate,Future security risks will be greater,So measures must be taken to prevent security issues.
First,It is not realistic to eliminate thermal runaway from the individual level of lithium-ion batteries at present,We can prevent induction and spread from the thermal electromechanical design and control design of the battery system,Even if a single unit experiences thermal runaway, accidents will not occur.
secondly,Starting from improving the safety of the battery itself,We need to develop new types of solid-state electrolyte batteries. Recently, we discussed with Japanese experts,Japan responds to the rise of China and South Korea's battery industry,Mobilize national efforts to develop the next generation of solid-state batteries,Annual government funding reaches50Billion~100Billion yen. The existing battery industries in the United States and Europe are relatively weak,They are also making every effort to develop a new generation of solid-state batteries,To achieve transcendence.
Although China's battery industry has temporarily gained advantages,But the competition pressure is enormous,We need to make every effort to catch up with the cutting-edge technology of solid-state batteries. Currently, there are also some solid-state batteries in China,But it's not an all solid state battery yet,Large scale commercialization of all solid state batteries is estimated to be in progress2025—2030Only in the year will it truly be realized,We need to make continuous efforts.
Based on the domestic and international situation,Overall,The development direction of battery positive electrode is to reduce cobalt to cobalt free,The negative electrode will be silicon doped,The content of silicon will gradually increase,Even all silicon. Electrolytes should reduce organic solvents,Gradually increase the concentration of lithium salt,But in the future, it may be necessary to develop all solid state electrolytes,However, there are still many technical bottlenecks that need to be overcome for all solid state electrolytes,It needs to be gradually developed.
Apart from batteries,What people are currently concerned about may be the range of endurance,Solving the battery cannot solve all the problems of driving range,At present, the range has increased from150Increase the mileage to universal300Over kilometers,However, customer complaints did not decrease accordingly,Because the actual range is lower than the expected value. Increasing battery capacity to increase range is not the fundamental solution,The mainstream technological route is to improve the energy efficiency and charging convenience of electric vehicles.
First,In terms of energy efficiency,The technological transformation of electric drive systems will be in the future5Annual occurrence,Namely, the high-speed, compact, and miniaturized motor drive system,Now the speed can reach1.8Wan Zhuan/minute,The future may come2Wan Zhuan/minute;The volume and weight of the motor gradually decrease,Due to the decrease in the cost of motor materials,The cost of the motor will also decrease.
secondly,The new generation of high-frequency and power electronics represented by silicon carbide will be widely used,This will also support the development of high-speed motors,Develop motors towards miniaturization and low cost.
Additionally, there is thermal management,The new generation of heat pump air conditioning technology has made significant breakthroughs,And start promoting industrialization,There are already companies loading vehicles now,This will reduce sensitivity to temperature,Reduce the loss of range in low-temperature winter environments compared to now2/3,from30%reduce to10%Another breakthrough is the integrated technology for optimizing vehicle energy efficiency,It can be said that power consumption is an important indicator of the level of vehicle integration technology,Energy saving of electric vehicles is more important than fuel vehicles,Regulations should be adopted for management.
Another factor is the convenience of charging,One is the construction of the charging system,The second breakthrough is the fast charging technology. China is220Voltage of volts,Very suitable for low-power slow charging. We should try to equip all family cars with slow charging stations as much as possible now,This will become the main power supply mode,Become the terminal node of energy Internet in the future;10～15Fast charging in minutes is *,But the positioning of fast charging is emergency,Not the main charging mode,The proportion of fast charging is roughly borne by15%～20%Currently350The cost of kilowatt DC fast charging and battery swapping is too high,Not ideal yet. Expected in the future5～7year,Safe and reliable fast charging technology will emerge,There is a lot of room for innovation in this area.
Toward the Future,Let's make a brief outlook on the roadmap for the marketization of electric vehicles. Domestic and foreign research shows that, two thousand and twenty-fiveThe price of the annual battery system will reach100dollar/Around kilowatt hours,In fact, the era of lithium iron phosphate in our country will be reached earlier. Cost based on the entire lifecycle,Calculate the price and full lifecycle cost of fuel vehicles,Fuel powered and electric vehicles will be on par,In addition, strict emission regulations are about to be implemented,The cost of fuel engines will increase,The turning point is approaching. We believe that2025About a year,Pure electric vehicles will achieve significant breakthroughs in cost-effectiveness.
Outlook on Hybrid Power Technology
Hybrid power is generally quite complex,Especially for non automotive and non engine industry professionals,Easy to confuse. Firstly, conventional hybrid power,Non rechargeable hybrid power,Toyota, Honda, and Nissan in Japan have respectively developed representative deep hybrid technologies,The trend of conventional hybrid power. But we also see that,Since last year,Japanese trial production of series NissanE-powerThe sales and fuel consumption can be comparable to Prius' power split products,This means that we don't necessarily have to take the route of power splitting,For China, connecting is relatively simple.
Another option is hybrid power that can be charged externally,We call it plug-in hybrid. Plug in hybrid power is divided into two stages,During the battery maintenance phase, it is a conventional hybrid power. But after charging,Using batteries,This paragraph is very important. This needs to be divided into two parts,One is pure electric plug-in type,It means all electricity is used,The stage after being fully charged is pure electric,But there are still some hybrid plug-in types,The front is still hybrid. We believe,Pure plug-in hybrid power for short distance electricity consumption in urban areas,High speed and long-distance oil,According to the characteristics of passenger car travel in China,Can save fuel80%above,This is China's advantageous technological route. If pure electric plug-in hybrid power is analyzed separately by function and structure,There are actually nine types of hybrid power,Pure electric hybrid power can be connected in series or parallel,It can also be mixed together. According to China's definition of extended programming,Actually, a series connected pure electric plug-in hybrid power,It is a type of pure electric plug-in hybrid power. China may mainly have two types: parallel and series,Hybrid will not become mainstream.
Comparing these two methods reveals,In hybrid mode,Parallel pure electric type compared to series pure electric type,Having cost and power advantages,Domestic enterprises are focusing on exploring low-cost pure electric parallel plug-in hybrid power,I think this is a very noteworthy technological route with Chinese advantages.
How to implement the hybrid technology roadmap?One is the energy-saving vehicle route after upgrading from fuel powered vehicles,From conventional hybrid to plug-in hybrid. The other is the hybrid route transitioning from pure electric vehicles,From pure electric to range extender and pure electric plug-in hybrid. Specifically,To develop through modularization and platformization,Internal combustion engine power can be developed into three parallel configurations through modularization,P2TheP2.5andP3,Later developed into parallel pure electric plug-in hybrid power.
in short,The characteristic and advantage of China's hybrid technology is still pure electric drive. Of course, pure electric drive includes pure electric,But it does not mean pure electric.
in addition,It must be mentioned that the core technology of hybrid power,That is, engine technology. At present, the efficiency of hybrid engines used in China is35%～37%,level38%～41%,Maximum efficiency of internal combustion engine:Diesel engine is approximately55%,gasoline engine45～50%,There is still a lot of room,We still need to innovate vigorously.
In terms of hybrid engines,Now the effective efficiency has exceeded45%,The main technological paths include increasing compression ratio, lean combustion turbocharging, and lean combustion compression ignition. It is worth mentioning that range extender electric vehicles may be low-power range extenders,We are currently exploring rotary engines, free piston engines, and so on,From the perspectives of literature analysis and self research,We believe that the mainstream technological route is still small displacement four stroke gasoline engines.