System and procedure for the thermal management of electric vehicle batteries
Patent Information
- Authority / Receiving Office
- DE · DE
- Patent Type
- Patents
- Current Assignee / Owner
- LIGHTENING ENERGY
- Filing Date
- 2015-09-29
- Publication Date
- 2026-07-09
AI Technical Summary
Existing electric vehicle battery charging systems face challenges in efficiently managing high heat dissipation during fast charging, leading to potential thermal runaway and increased vehicle weight and cost due to the need for larger, heavier onboard cooling systems.
An off-board coolant management system supplies coolant at a higher flow rate than onboard systems, determining optimal coolant type and flow rates based on vehicle parameters, and includes a control system to regulate temperature and flow, minimizing weight and cost by using external cooling infrastructure.
Enables rapid charging without increasing vehicle weight or cost by efficiently managing heat dissipation, allowing faster charging times and reducing the need for larger onboard cooling systems, thus enhancing safety and performance.
Abstract
Description
[0001] The present invention relates generally to the temperature management of electric vehicle batteries and in particular to the external temperature management of electric vehicle batteries during charging. BACKGROUND
[0002] US Patent No. 8,448,696 discloses a vehicle-integrated thermal management system.
[0003] US Patent No. 8,174,235 discloses a system and a method for charging battery-powered electric vehicles in which an external coolant is supplied; US Patent No. 8,350,526 discloses a station for fast-charging an electric vehicle battery in which an external coolant is supplied; and US Publication No. 2013 / 0029193 discloses an electric vehicle and an electric vehicle battery that are cooled with an external coolant during charging. DESCRIPTION OF THE INVENTION
[0004] According to a first feature of the present invention, a method for supplying coolant to an electric battery supplying electrical energy to a powertrain of an electric vehicle is provided, which includes, for cooling the electric battery during charging, the supply of coolant from a coolant source located outside the electric vehicle at a first rate, and, for cooling the electric battery after charging, includes the circulation of coolant through an internal coolant circuit of the electric vehicle at a second rate, which is lower than the first rate.
[0005] According to a second feature of the present invention, a method for supplying coolant to an electric battery supplying electrical energy to a powertrain of an electric vehicle is provided, which includes, for cooling the electric battery, the supply of coolant from an external coolant source to an internal coolant circuit as a function of parameters of the internal coolant circuit.
[0006] According to a third feature of the present invention, a method for supplying coolant to an electric battery supplying electrical energy to a powertrain of an electric vehicle is provided, which includes determining a type of coolant in an internal coolant circuit of the electric vehicle which is in fluid communication with the electric battery, selecting the specific type of coolant from several external coolant sources, and supplying the specific type of coolant from an external coolant source to the internal coolant circuit of the electric vehicle.
[0007] According to a fourth feature of the present invention, a method for supplying coolant to an electric battery supplying electrical energy to a powertrain of an electric vehicle is provided, which includes determining a heat dissipation rate of the electric battery caused by charging the electric battery at a predetermined charging rate, determining a convective heat transfer coefficient for dissipating the heat dissipated by the electric battery during charging, determining a maximum permissible flow rate of the vehicle's internal coolant circuit, determining whether an optimal flow rate of the coolant from an external coolant source meets the conditions of the convective heat transfer coefficient and the maximum permissible flow rate, and charging the electric battery at the predetermined charging rate.if the optimal flow rate of the coolant from an external coolant source corresponds to the conditions of the convective heat transfer coefficient and the maximum permissible flow rate, wherein charging the electric battery includes the supply of coolant from the external coolant source at the optimal flow rate. BRIEF DESCRIPTION OF THE DRAWINGS
[0008] The present invention is explained in more detail below with reference to the accompanying figures.
[0009] Fig. Figure 1 shows an in-vehicle temperature management system according to an embodiment of the present invention,
[0010] Fig. 2 shows a flowchart representing a method according to an embodiment of the present invention and
[0011] Fig.Figure 3 schematically shows an external system in the form of a fast charging station for charging an electric vehicle, including the [unclear - possibly "in" or "in"]. Fig. 1 vehicle-internal temperature management system shown according to an embodiment of the present invention. DETAILED DESCRIPTION
[0012] Thermal management is a crucial challenge when it comes to achieving faster charging speeds for electric vehicles. Faster charging leads to increased heat dissipation within the battery. For example, the Tesla Model S currently uses an in-vehicle cooling system. An external cooling system, with the addition of extra pumps, can generate a higher flow rate than the Model S's internal pumps can deliver. Since high-performance in-vehicle pumps add weight, using an external cooling system can be an effective way to reduce vehicle weight. To enable faster charging at rates higher than those offered by Superchargers, highly efficient battery cooling is essential.A higher flow rate also increases convection between the coolant and the cells, resulting in both greater heat transfer between the coolant and the cells and a lower temperature gradient between the inlets and outlets of the coolant pipes circulating within the modules. Another advantage of this invention is that a larger quantity of fluid can be stored in the vehicle's external system without increasing the vehicle's weight. Furthermore, embodiments of the invention can be used to heat the battery at a higher rate when charging in cold climates. Additionally, the vehicle's internal heat exchanger might require significantly higher cooling capacity to enable charging at rates higher than those of current superchargers. This heat exchanger could also increase the vehicle's weight and consume more space that could alternatively be used for more batteries.Furthermore, the cost reduction for the vehicle can provide an incentive to use an external cooling system.
[0013] For example, the 85 kWh battery pack of the Tesla Model S requires a coolant inlet temperature of 9 degrees Celsius when charging at 300 kW to prevent thermal runaway in any of the cells. The proposed 300 kW charger corresponds to a charging time of approximately 20 minutes for a full charge of an 85 kWh battery pack. Tesla offers a Supercharger that, under ideal conditions, takes approximately 30 to 40 minutes to charge to 80%. Around 100 of these charging stations have been installed between the West and East Coasts (figures refer to the USA). With a 300 kW charger, charging an 85 kWh battery pack to 80% takes on the order of 10 to 15 minutes. The embodiments of the invention are not limited to this charging rate and preferably include charging rates of less than 5 minutes.
[0014] Depending on the specified amount of coolant, the Model S's internal heat exchanger might not be able to reach the required temperature, necessitating an external cooling system. During charging at a Tesla Supercharger, up to 13 kW of heat is generated, and at 300 kW charging, this figure exceeds 50 kW. Without external cooling, this additional weight would have to be added to the vehicle's internal system. The pumps would have to operate at their maximum capacity for extended periods, leading to increased wear and tear. Enlarging the internal cooling system would increase both the vehicle's cost and weight, ultimately raising its overall price.
[0015] Fig. Figure 1 shows an in-vehicle temperature management system 100according to an embodiment of the present invention, which is connectable to an external coolant source of an external temperature management system, such as is found, for example, in Fig. Figure 3 shows an external cooling circuit. 102 circulates to cool an on-board charger 104 An internal cooling circuit is coupled to the vehicle's external cooling circuit. 105 (cf.) Fig. 1) which has at least one battery 106 a battery pack that at least partially supplies energy to the electric vehicle's powertrain. According to this embodiment, a pump 108 of the cooling circuit 105 ( Fig. 1) The vehicle will start operating once the vehicle's external cooling system has been properly connected to the vehicle's system. As described in Fig. Figure 1 shows an inlet valve. 110 for the cooling circuit 105 the pump 108downstream and upstream of the heating system. In this embodiment, the valve is 110 This could be a three-way valve, but it could also be any valve capable of shutting off the flow from the vehicle's internal system and allowing the external coolant to enter. In this embodiment, the external coolant is the same as the vehicle's internal coolant.
[0016] The coolant flows through the battery pack. 106 with a higher flow rate made possible by the vehicle's external pump. After the coolant had passed through the battery pack. 106 Once this has happened, it returns to the vehicle's external reservoir (e.g., source). 64 in Fig. 3) via an exhaust valve 112The valve in this embodiment is a three-way valve. Further embodiments of the invention may include the possibility of having multiple inlet and outlet valves. A larger number of valves can reduce the temperature gradient within the battery.
[0017] There are numerous important parameters involved in determining and controlling the maximum tolerable charging rate of an electric vehicle. The vehicle's external system first determines the type of coolant used in the vehicle. This can be determined using the owner's manual database. Once the system has this information, it can access a database containing all the coolant's properties, such as heat transfer coefficients, density, and viscosity. Most of these coefficients can be found in manuals like ASHRAE. Some heat transfer coefficients may need to be determined experimentally, and the results can then be entered into the database. Another parameter determined by the vehicle's external system is the rate at which it will pump coolant into the vehicle's system. Determining this involves a calculation based on several vehicle parameters.The maximum flow rate can be determined by the maximum power of the vehicle's external pump, as well as the losses in the vehicle's internal piping system, including parameters such as the cross-sectional area and length of the pipes. Once this maximum flow rate has been determined, the temperature change of the coolant between the inlet and outlet can be calculated. The characteristics of the piping / line system for the coolant must also be considered. For example, the coolant flow rate may be limited by the maximum pressure at which coolant can be pumped through the vehicle's internal piping system.
[0018] The vehicle's external system can also determine and control the temperature at which the coolant is pumped. This requires considering the material properties of the vehicle's cooling system. To determine the necessary coolant temperature, the surface area in contact with each battery, as well as the thermal conductivity of all contacting materials, are used. Other relevant properties include the mass of each battery, its specific heat capacity, its internal resistance, and its charging current.
[0019] Another parameter considered when supplying coolant is the chemical composition of the batteries on board the electric vehicle. Certain battery chemical compositions tolerate a maximum charging rate. The vehicle's external system can use this chemical composition to determine the current and voltage to be supplied to the vehicle's internal batteries.
[0020] According to embodiments of the present invention, this information can be compiled in a database which the charging station can access before the start of fast charging.
[0021] Embodiments of the present invention may also include a control system capable of monitoring the coolant temperature and the cell temperature at various points within the battery pack to ensure safety during this fast-charging process. The vehicle-external system may include controls for regulating the flow rate and the coolant temperature. The sensors on board the vehicle may transmit information to the vehicle-external system for regulating the flow rate and temperature.
[0022] Furthermore, it is possible to integrate a heat recovery system into the vehicle's external thermal management system. Since heat loss during charging is considerable, this waste heat could be extracted via the coolant leaving the vehicle after charging.
[0023] The vehicle-integrated fast-charging system can first identify the vehicle type that has just arrived at the charging station. This can be done by scanning a transponder, also known as an RFID tag (RFID stands for radio-frequency identification, identification via electromagnetic waves), or a vehicle identification number (VIN). Alternatively, a user interface can be used, allowing the vehicle owner to enter the vehicle type into the system. If a scanning system is used, a vehicle can approach the station, and a portal above the vehicle may have an antenna similar to those used at toll booths. Each electric vehicle owner can purchase a chip, similar to a vignette or an e-ZPass (for the US toll system), to identify the vehicle, or, as described below, Fig.As shown in Figure 3, an RFID tag may be provided that is attached to the battery or to other parts of the temperature management system. 100 It is attached to the vehicle's chassis. The owner can then pay for fast charging using an account linked to the RFID tag.
[0024] The RFID tag can also be located on the windshield near the rearview mirror. Alternatively, the charging station can include a user interface that incorporates, but is not limited to, smartphone applications or on-site touchscreens. The user can then select the type of electric vehicle from a list, and from there a database could be accessed.
[0025] The account associated with the RFID tag can contain information such as vehicle make and model, as well as year of manufacture.
[0026] Once the vehicle has been identified using the procedures described above, the charging system can access a database containing information about the necessary characteristics of the respective electric vehicle. The database may include, but is not limited to, the information listed in Table 1 below. Such information may be necessary to determine the required coolant temperature and flow rate during the charging process. Information not listed in this table can be determined through laboratory experiments, which will then be used to populate the database. Furthermore, data can be obtained from other databases, such as electric vehicle datasheets, owner's manuals, parts lists, or other sources. Such a database may contain main categories such as vehicle type, vehicle components, and the properties and values assigned to these components. Electric vehicle database category Characteristics Data / Value Vehicle brand Tesla Vehicle model Model S Year of construction 2013 Coolant type Ethylene Glycol – G48 Coolant properties density 1.1 g / cm^3 viscosity 12.95 mPa / s Pump specifications maximum continuous power 800 W Information on the vehicle cooling system Pipe length per module 7,2 m Pipe material copper silicone elastomer mixture silicone adhesive Properties of the piping material Thermal conductivity of copper 385 W / mK Thermal conductivity of silicone elastomer 1 / 3 W / mK Thermal conductivity of adhesives 1.8 W / mK Cross-sectional area of the pipelines 1.2 e–4m^2 Cooling capacity heat exchanger look up / determine maximum permissible pressure in pipes look up / determine Information on the vehicle battery internal chemistry Nickel-cobalt-aluminum oxide / maximum charging rate maximum charging rate without damage 120 kW specific heat of a battery 0.823 J / gC Cell mass 45,0 g Charging current / charging voltage for system 297.6 A / 403.2 V Number of cells / modules / configuration 7104 cells / 16 modules Internal resistance 60 milliohms maximum permissible cell temperature 40 degrees Celsius minimum permissible cell temperature look up / determine contacting surface between 0,0006655 m 2 cells and cooling lines Entropy caused by cells as a maximum -68.31 kJ / mol Function of the charge level Table 1
[0027] Fig. Figure 2 shows a flowchart illustrating a method according to an embodiment of the present invention. The method includes an algorithm that can perform calculations after accessing the data listed in Table 1 from the database. The flowchart above shows that a first step 401 This includes access to the maximum charging rate information in the database. This information can be used to obtain data on the maximum permissible current and voltage that the system can use to charge the vehicle. This voltage and current information, along with other values from the database, can be used to... 402 or to obtain the heat dissipation rate q during this fast charging phase (T_cell = cell temperature): = I 2 R + T cell ΔSF 1 F
[0028] Step 403This involves determining the limiting factor for the maximum permissible flow rate through the pipe system. This depends on the pump output, the thickness of the pipe materials, and the cooling capacity of the heat exchanger. The limiting factors of the proposed external system can be the pump output of the external system and the maximum pressure tolerable by the internal piping. The following is a sample calculation for determining the maximum flow velocity as a function of a given pump output, based on several parameters obtained from the database.
[0029] Now solve for velocity V:
[0030] Based on the above values and the pump efficiency η, V max The problem has been resolved. The pump efficiency is now 100%. V max = 4,308 m / s
[0031] An alternative limiting factor in step 403 This can be the maximum pressure tolerable through the piping of the vehicle's internal cooling system. In the case of the Tesla Model S, for example, the piping is made of some type of metal, including but not limited to copper or aluminum; and it is 0.5 mm thick. Based on the above in step 403 The calculated flow velocity allows the pressure within the pipe system to be determined (strength = strength, thickness = thickness, safety factor = safety factor):
[0032] In this specific case of a copper pipe, the pipe's burst pressure is higher than the maximum pressure exerted by the coolant flow rate. In other cases, this could be different, and this pressure might limit the maximum flow rate.
[0033] To achieve the necessary convective heat transfer coefficient 404To determine the coefficient, the database can access experimental research, or a calculation can be applied to empirically derive it. Further necessary heat transfer coefficients of the piping material can also be accessed via the database at this stage.
[0034] Step 405 This includes selecting the optimal one, in steps. 403 and 404 The coolant flow rate corresponds to the specified conditions. The coolant flow rate does not exceed the maximum permissible flow rate and yet still meets the required heat transfer coefficient. If the required heat transfer coefficient cannot be achieved under certain circumstances with a flow rate below the maximum, then the procedure described in step 401 The specific maximum charging rate will be recalculated and the process can be restarted at step 401begin. The optimal flow rate 405 can be achieved with a predetermined safety factor above the minimum necessary heat transfer coefficient. 403 and the maximum flow rate 404 be elected.
[0035] Once the flow rate in step 405 The required outlet temperature can be determined using values from the database. 406The coolant temperature is calculated. This temperature represents the highest temperature the coolant may reach to prevent overheating and ensure safe charging all the way to the last cell in the cooling circuit. The following is an example equation for determining the coolant outlet temperature with T_coolant (coolant temperature) as the unknown variable. All values in the denominator represent various coefficients and pipe thicknesses. These values depend on the different thermal layers between the battery cells and the cooling system and can vary depending on the vehicle type (T_cell = cell temperature, T_coolant = coolant temperature):
[0036] Step 407This includes calculating the total amount of coolant in the pipes adjacent to the battery pack. This specific amount is important because it represents the amount of coolant that absorbs the heat generated by the battery pack during the charging process.
[0037] This quantity can be used to determine the temperature gradient. 408 The temperature gradient between the inlet and outlet of the coolant pipe in each module of the battery pack must be determined. This temperature gradient can be minimized by maximizing the flow rate through the coolant pipes. An example calculation for determining this temperature gradient is shown here, with the values on the left either taken from a database or from previous calculations. In this case, the calculation gives the estimated coolant temperature gradient when using a 300 kW charger.
[0038] With the final calculation409 The necessary coolant inlet temperature can be determined. This can be the temperature of the coolant at which it can be pumped from outside the vehicle into the vehicle's internal cooling system. The external system can then deliver the coolant at the necessary pressure and temperature through the pipes connected to the vehicle. 410 ).
[0039] The control system connecting the vehicle to the external system can continuously monitor the coolant temperature and the cell temperatures at various points within the vehicle. If one of the cell temperatures becomes too high, the system can increase the coolant flow rate, provided it is still below the maximum. If the flow rate cannot be increased, the charging process can be temporarily stopped until a more stable temperature is reached.
[0040] Fig.Figure 3 schematically shows an external vehicle system in the form of a fast charging station. 60 for charging an electric vehicle 20 including the vehicle's internal temperature management system 100 according to one embodiment of the present invention. In the preferred embodiment of the present invention, the electric vehicle 20 a purely electric vehicle 20 , whose drive is powered by an electric vehicle battery pack 106 (see Fig. 1) is supplied with energy, but does not have an internal combustion engine. In an alternative embodiment, the electric vehicle 20 be a hybrid electric vehicle that combines an electric vehicle battery pack 106 may include a cooperating internal combustion engine.
[0041] The fast charging station 60 can a system 62 for electrical power supply for fast charging of battery packs 106 of the vehicle20 include an external temperature management system 64 for supplying heat exchanger fluid to the battery pack 106 , if the battery pack 106 The vehicle's electrical power supply system allows for rapid charging. 20 can the fast charging station 60 start the vehicle 20 switch off and make a connection 42 at one end of a feeder 68 the fast charging station 60 into a corresponding one, from outside the vehicle 20 accessible recording 50 into the vehicle 20 introduce. In the Fig. In the embodiment shown in section 3, the feed leads to the 68 from a base area 72 out and includes an electrical feed 68a , which can be a cable connected to the electrical power supply system 62 is coupled, and a feed 68bfor heat exchanger fluid, which supply 68b a hose that connects to an external coolant supply for the vehicle 64 is coupled. The driver can disconnect the connection. 42 so into the recording 50 of the vehicle 20 introduce that the connection 42 temporarily admitted 50 clicks into place. The recording 50 can be used with one or more grooves 52 be trained to receive a corresponding number of connections 42 radially projecting protrusions 44 serve. The protrusions 44 can at the connection 42 They must be attached under spring pressure so that they, upon contact with the outside of the opening of the receiver, 50 radially into the connection 42 be pressed in and then radially outwards into the grooves 52 snap into place as soon as the connection is made 42 into the recording 50is introduced. It can also be one introduced by the driver of the vehicle. 20 trigger to be activated 46 for locking and unlocking the projections 44 It is provided that in this embodiment it is a push button on the connector 42 is trained, upon whose activation the projections 44 to insert the connector 42 into the recording 50 are retracted, where they remain after insertion when the trigger is released. 46 into the grooves 52 can push. After the connection 42 in the recording 50 is locked in such a way that the grooves 52 cooperating protrusions 44 prevent the connection 42 from the recording 50 If the vehicle slips, the driver can 20 activate a trigger for charging / cooling, which in this version serves as a handle. 48 is trained, who captures and moves towards the connection 42can be pressed to stop the flow of electricity from the electrical power supply system 62 as well as the flow of heat exchanger fluid from the vehicle's external coolant supply 64 to the battery pack 106 to set in motion.
[0042] If the heat exchanger fluid passes through the battery pack 106 has flowed through and the outlets of the battery pack 106 Having exited, it passes the outlet of the exhaust valve. 112 (see Fig. 1) The heated heat exchanger fluid is then circulated by means of a return pump. 75 from a drainage section 96 for heat exchanger fluid in the intake 50 out and into a return section 86 for heat exchanger fluid in one connection 42 pumped in, and then through a return line 68c into the vehicle's external coolant supply 64returned. The coolant supply for the vehicle's external system. 64 The recirculated heat exchanger fluid is thermally treated for reuse.
[0043] A control unit 70 It may be provided which the battery pack 106 from the electrical power supply system 62 The supplied charge quantity is controlled, and the supply of coolant from the vehicle's external coolant supply is controlled. 64 as described above. The control unit 70 can also be used with a touchscreen 71 and a credit card reader 73 be coupled. As also explained above, the control unit can 70 It may also be coupled with a detector, for example in the form of a radio wave-based RFID reader, which is connected to an information source in the form of an RFID tag. 79 a vehicle 20The communication between the reader and the RFID tag can serve to input data for controlling one or more parameters of the charging process, the heat exchanger fluid, and the transaction. The detector and the information source can employ a variety of alternative or combined forms of detection and communication, for example, optical, magnetic, acoustic, or pattern recognition-based methods, or they can be detectors and compatible information sources of another type.
[0044] If the fast charging station 60 The fast charging station begins the charging process 60 the battery pack 106 electricity from an electrical power supply system 62 and heat exchanger fluid from an external vehicle coolant supply 64 to, until the battery pack 106 is sufficiently charged. An external pump for the vehicle. 74with a higher pumping capacity than the vehicle's internal pump 108 (see Fig. 1) – i.e., the pump 74 It can pump heat exchanger fluid at a higher rate than the vehicle's internal pump. 108 – pumps heat exchanger fluid through the supply 68b for heat exchanger fluid. The vehicle-external system 60 leads to this during the charging of the battery pack 106 Coolant from outside the electric vehicle 20 located coolant source 64 with an initial rate for cooling the electric batteries of the battery pack 106 to. The vehicle's internal system 100 circulates to cool the electrical batteries of the battery pack 106 After charging the electric batteries, the coolant passes through the internal coolant circuit. 105 of the electric vehicle 20with a second rate that is lower than the first rate. The heat exchanger fluid leaves the heat exchanger fluid supply. 68b at a feed section 84 for the heat exchanger fluid afterwards 42 and enters the inlet of the valve. 110 (see Fig. 1) of the system 100 in the vehicle 20 at an inflow section 94 for the heat exchanger fluid in the intake 50 The heat exchanger fluid supply line is connected to an inlet of the battery pack. 106 coupled and leads the battery pack 106 Heat exchanger fluid. A power supply unit. 76 carries electricity from the electrical power supply system 62 through the electrical supply 68a The current leaves the electrical supply. 68a in the section of an electrical supply 82 in connection 42 and enters an electrical line24 into the vehicle 20 a section of an electric current flow 92 in the recording 50 To prevent the connection 42 from the recording 50 is removed while the vehicle 20 When electricity and heat exchanger fluid are supplied, care is taken to ensure that the projections 44 did not unlock during charging and plugged back in. 42 can be withdrawn. The connection 42 can additionally be equipped with spring-loaded couplings on the feed section 84 the heat exchanger fluid or nearby, with the couplings being removed from the connection. 42 from the recording 50 a rapid sealing of the heat exchanger fluid supply section 84 to enable and thus prevent the leakage of heat exchanger fluid.
[0045] Embodiments of the invention may include other charging stations, including, but not limited to, home charging stations. These home charging stations may be specifically tailored to the type of vehicle being charged by the user.
[0046] The home charging stations can draw power from the grid at a lower rate or current during off-hours to recharge an associated battery pack, which would rapidly discharge when used to charge the vehicle's batteries.
[0047] One of the primary advantages of the embodiments of the invention is the potential savings in weight, cost, and volume that can be achieved without upgrading the internal system of the electric vehicle. An improved heat exchanger capable of tolerating higher charging rates can be provided. The heat exchanger can be designed to provide the cooling capacity necessary to absorb the 50 kW or more of heat generated during a 300 kW charging process. Similarly, heat exchangers capable of handling a charging rate of 120 kW can be used.
[0048] A heat exchanger with a cooling capacity of 50 kW requires considerable space. Such a heat exchanger, capable of dissipating 50 kW of heat, can be up to 0.226 m² larger compared to one capable of dissipating only 8 kW. 3additional space is required. This additional space requirement then reduces either the available trunk space or the performance of the vehicle battery. If this space requirement is subtracted from the battery capacity, this can lead to a performance loss of up to 29.73 kWh or 93 miles (approximately 150 km) of range. Table 2 summarizes the advantages of an exemplary embodiment of the present invention and, in particular, of an external cooling system. Weight saving 23 kg or 50.7 lbs Cost savings 2,700 US $ / approx. 2,530 € Volume saving 0,2212 m^3 Additional performance through volume savings 29.73 kWh or 93 miles / 149.669 km range Table 2
[0049] The invention has been described in the preceding sections with reference to specific embodiments and examples thereof. However, it is entirely conceivable that modifications or alterations of the invention can be made without departing from the scope of protection defined in the following claims. The description and the figures illustrate and clarify exemplary embodiments of the present invention, which are not to be understood as limiting, in their details and functions.
Claims
[1] Method for supplying coolant to an electric battery supplying electrical energy to a powertrain of an electric vehicle, comprising: Supply of coolant from a coolant source located outside the electric vehicle with a first rate for cooling the electric battery during charging of the electric battery as well as Circulation of coolant through an internal coolant circuit with a second rate that is lower than the first rate, for cooling the electric battery after charging the electric battery. [2] Method according to claim 1, wherein a first pump located outside the electric vehicle with a first pumping capacity supplies the coolant during the charging of the electric battery at the first rate, and a second pump in the internal coolant circuit of the electric vehicle with a second pumping capacity supplies the coolant after the charging of the electric battery at the second rate, wherein the first pumping capacity is higher than the second pumping capacity. [3] Method according to claim 2, wherein the supply of coolant from the coolant source located outside the electric vehicle at the first rate includes the introduction of coolant into the coolant circuit at an inlet valve located upstream of the electric battery. [4] Method according to claim 3, further comprising the supply of the coolant leaving the electric battery to the coolant source located outside the electric vehicle during the charging of the electric battery. [5] Method according to claim 4, wherein the supply of the coolant leaving the electric battery to the coolant source located outside the electric vehicle includes the control of an outlet value in the coolant circuit downstream of the electric battery in order to direct the coolant from the coolant circuit to the coolant source located outside the electric vehicle. [6] Method for supplying coolant to an electric battery supplying electrical energy to a powertrain of an electric vehicle, comprising: Supply of coolant from an external coolant source to an internal coolant circuit for cooling the electric battery as a function of parameters of the internal coolant circuit. [7] Method according to claim 6, wherein the parameters include at least one of the parameters of a coolant in the vehicle's internal coolant circuit as well as parameters of at least one structure forming the vehicle's internal coolant circuit. [8] Method according to claim 6, further comprising retrieving information relating to parameters of the vehicle's internal coolant circuit on a computer-readable data carrier, wherein the supply includes automatic pumping of the coolant from the vehicle's external coolant source at at least one rate or temperature as a function of the parameters of the vehicle's internal coolant circuit. [9] Method for supplying coolant to an electric battery supplying electrical energy to a powertrain of an electric vehicle, comprising: Determination of a coolant type in an internal coolant circuit of the electric vehicle that exchanges heat with the electric battery; Selection of the specific type of coolant from several external coolant sources; Supply of a specific type of coolant from an external coolant source to the internal coolant circuit of the electric vehicle. [10] Method according to claim 9, further comprising retrieving information relating to coolant parameters from a computer-readable data carrier following the selection of the specific coolant type, wherein the supply includes automatic pumping of the specific coolant type from the vehicle-external coolant source at at least one rate or temperature as a function of the coolant parameters. [11] Method for supplying coolant to an electric battery supplying electrical energy to a powertrain of an electric vehicle, comprising: Determination of the heat dissipation rate of the electric battery caused by charging the electric battery at a predetermined charging rate; Determination of a convective heat transfer coefficient for dissipating the heat emitted by the electric battery during charging; Determination of a maximum permissible flow rate of the vehicle's internal coolant circuit; Determining whether an optimal coolant flow rate from an external coolant source meets the conditions of the convective heat transfer coefficient and the maximum permissible flow rate and Charging the electric battery at the specified charging rate, provided that the optimal flow rate of the coolant from an external coolant source meets the conditions of the convective heat transfer coefficient and the maximum permissible flow rate, wherein charging the electric battery includes the supply of coolant from the external coolant source at the optimal flow rate.