cloud network hunting note: tesla claims that share the patent technology, to promote the development of electric vehicle industry, a stone up, what are the core patent that tesla? Hunting share an article in the industry xu-hui zhou cloud network, look at those tesla patents owned by ordinary people don’t understand.
we statistics, Tesla during 2008-2013 for core intellectual property rights are mostly related to the battery safety control system, including battery cooling system, security system, charge balance system, etc. By the end of March 2013 Tesla for 142 such patents, with another 258 patents are under approval process.
in addition to the battery management system, Tesla in motor and electric control of some ingenious technology.
Tesla motors for independent research and development of three-phase induction motor, the motor has a coil linear optimization, to minimize resistance and energy loss. Electrical energy use efficiency is low, reduces the power of high capacity battery performance advantages, needs strong power system equipped with intelligent power management software will be current of each battery monomer digitization and battery power effectively converted into auto kinetic energy, improve energy utilization efficiency.
gearbox for single variable speed system, can will be produced by the ac induction motor torque and speed the optimization of matching, compared to conventional gasoline gearbox has better accelerated motion characteristics. Additionally installed on Tesla motors with a complete hardware and software system, including the rotation frequency converter, digital signal processing system and charging system, is used to control the torque of the motor and battery energy transfer process, is the energy of the car body control system. Through a high performance digital signal processor can be car braking, braking, acceleration and deceleration into digital signals, which control the rotation frequency converter will battery dc and ac transformation to drive power, provide the corresponding three-phase induction motor cars also through rotational frequency converter can be produced by regenerative braking system of alternating current into direct current to complete charge and discharge process.
a, tesla’s solution: a small battery + BMS
Tesla battery USES is panasonic ternary material (aluminum nickel and cobalt acid lithium), with the 18650 model is more mature (panasonic this battery widely used in notebook).
unlike now the mainstream trend of electric vehicle batteries, Tesla is the only one using 18650 type lithium ion battery company directly and other electric vehicles with large battery. But Tesla costs more than 7000 section 7000 lithium batteries. Ordinary household laptops as long as 7 ~ 8 knots.
Tesla USES small battery reason lies in:
mature process. in the past 15 years that has accumulated in consumer products of advanced technology can be used in car batteries, consumer products can boost demand, reduce cost and increase the energy density. But now many of the newly developed large capacity type battery, only belong to the experimental products, did not have excessive production experience, can not reach the mature stage. Panasonic is the world’s battery technology and one of the largest enterprises, product defect at least, due to large scale, also easy to pick out the consistent good battery.
high performance-price ratio. the Model S 85 kWh models battery power system total cost about $30000, unit of storage costs about $400 per kWh, is the other half of the electric vehicle energy storage cost. 18650 battery maker is numerous, the downstream enterprises to the upstream manufacturers have stronger bargaining power, the cost of the battery can be controlled. And with the popularity of electronic consumer products, 18650 prices will continue to slide, tesla may also benefit from the side.
safety control. the size of each cell is small, but each unit of energy can be controlled in the range of small, compared with when using large size cells, even if one unit of battery failure, also can reduce the effects of failure.
but small battery to many (7000) of monomer battery, will be a big increase in inconsistencies between the battery monomer, monomer temperature, charge, voltage imbalance, cause individual battery overcharge, discharge and electrostatic interactions, thus reducing battery life and safety.
2, core technologies: battery management system
this is the core technology of Tesla battery management system.
Elon musk itself is to learn physics, and for the hundreds of engineers in silicon valley, this is the root cause of its leading technology.
Tesla battery testing laboratory, data information center to intelligent monitoring of 18650 of its temperature.
2.1 battery testing laboratory: source increases lithium battery monomer consistency
due to the standard 18650 small capacity battery monomer (about 10.4 wh), Tesla Model S 85 KWH edition electric cars will require more than 8000 battery monomer. Of so many battery monomer battery pack, inconsistency between increase monomer substantially, easily lead to individual monomer overcharge, discharge and electrostatic interactions to reduce battery life and produce safe hidden trouble, thus to put forward the high requirements on the consistency of the monomer detection.
Tesla has an independent laboratory and theoretical basis for lithium batteries, lithium battery monomer chemical properties, the shape coefficient is set up a complete data information center, through the laboratory and data center will be provided by the battery supplier Sanyo 18650 battery strict performance test and the consistency of screening, focus on the indicators include: single capacity size, energy storage durability, power output, voltage lower limit on the size, etc. The consistency, security, good battery as a backup battery, the battery pack which fundamentally guarantee the stability of the battery power transmission and persistence.
2.2 charge balance system: effectively ruled out 18650 fault monomer
each monomer has a lithium-ion batteries voltage upper limit and lower limit, the battery can work normally in this scope, but once the monomer voltage is close to the limit its chemical properties will mutate, must immediately stop discharge or charge, otherwise will be irreversible damage to the battery, will substantially increase the battery self-discharge rate, and then an explosion caused by electrostatic interactions.
many of battery monomer battery greatly increases the inconsistency between monomer, lead to the safety of the battery voltage range each are not identical, security is greatly reduced. Tesla, independent research and development for this monomer charge balancing system, which can effectively troubleshoot monomer, ensure the safety of the vehicle performance. Tesla battery tail with printed circuit board, with the power switch, each power switch connects to a 18650 battery monomer, the other end connects a medium-sized collector (monitor) monomer charge. When the battery in a battery caused by overcharge, discharge, high temperature, not with other battery at the same time, the collector will be energy of mutual transfer between the battery, prevent the voltage range of security and produce change. When the battery really produce variation, electronic integrator will control circuit board photogenic corresponding power switch off, so the battery monomer isolation, avoid to produce electrostatic reaction caused by the explosion.
2.3 lithium battery temperature management system: improve vehicle safety performance
Tesla KWH of up to 60, 85 KWH battery capacity to make its operation process will release more heat and thus increase the probability of an explosion caused by the battery temperature is too high, this is Tesla battery management system to solve one of the most core question.
battery temperature detection system – intelligent temperature monitoring
the electric car safety is mainly manifested in the control of the battery temperature and current, especially for the large capacity of the battery module, when the battery charge and discharge, collision and batteries during the operation of excessive heat will cause the battery temperature is too high and explode.
Tesla car battery in each battery monomer is connected to a thermistor and a series of optical fiber, at the same time will monitor thermal resistor is connected to the battery, connect the optical fiber optical sensor. When a battery monomer temperature exceeded safety standards, thermistor to convey to produce an electrical signal to the battery monitor in order to start the battery condensing system to assure the safety of the battery performance. When the battery such as thermal runaway phenomenon occurs, will affect the beam of light in the fiber optic transmission, thus stimulating the photosensitive sensor signal corresponding to the heat. When car intense collision occurs, the energy of the battery and motor transmission path will be blocked immediately, outside the battery cover to protect the battery from collision impact, so as to avoid violent explosion.
battery liquid condensation system, the real-time temperature control
Tesla, independent research and development of the body’s liquid cooling system for dual mode cooling system, including the first layer cooling circuit designed for battery pack cool, battery circuit battery packs connected to cooling pump, loop is filled with coolant, and extend multiple cooling pipe to cover each battery monomer. First floor cooling circuit will be charged with heating system, ventilation and other heat radiator and battery management system, to ensure that each battery monomer temperature below the TVC, ensure the heat dissipation and safety performance. The second cooling circuit including the second cooling liquid storage tank and heat exchange with at least one rotating components, and in the first cooling circuit, ensure the independence of the battery cooling system.
Tesla company promises to Tesla Model S battery provides eight years or 100000 miles of quality assurance, the other car components provide 4 years or 50000 miles of quality assurance. Especially recently launched a free service plan, tesla will offer from loss due to poor maintenance of battery warranty, and will be free replacement of the same quality or better performance for clients battery, the battery quality.
final statement, I am as a securities practitioners discuss technology, theory, may not be professional, please comment more!