System and procedure for charging batteries for electric vehicles

Abstract

A method for charging an electric vehicle (20) with an electric battery (30) as a vehicle propulsion system, this method comprising: charging the electric vehicle (20) for an initial period with an initial electric current at a standard connection (56) with 120 or 240 volts;and charging the electric vehicle (20) over a second period, which is shorter than the first period, with a second electric current which is higher than the first electric current via a high-performance charging source (62) which differs from the standard connection (56), wherein during the second charging process the supply of a coolant to the electric vehicle (20) is provided in order to cool the electric battery (30) over this second period, wherein the electric battery (30) has a plurality of battery cells (32) which are separated by a plurality of internal channels (34) running between the battery cells (32), which channels (34) are at least partially provided with porous, compressible interconnectors (36) and through which channels (34) the coolant is passed to cool the battery cells (32) during the second period.

Description

The present invention relates generally to electric vehicles and, more particularly, to a system and method for charging batteries for electric vehicles.BACKGROUND OF THE INVENTIONThe further development of pure electric vehicles-that is to say vehicles which are operated exclusively by battery electricity, in contrast to the hybrid electric vehicles additionally equipped with internal combustion engines-is hindered by a wide variety of hurdles, especially if the developed electric vehicles are intended to be capable of being held on a mass market. One of the hurdles to be overcome is the so-called "range anxiety", i.e. the concern of the drivers not being able to reach their destination with the charge of the electric battery. While the energy consumption of the peripheral devices remains constant without its own drive (air conditioning system, heating, lighting, etc.), the actual range of the electric vehicle is variable and dependent on the driving style, and the range is often below the expectation of anxiety here, in particular when driving in densely populated areas with varying travel speeds. Due to this variation width, users of electric vehicles tend not to precisely predict the actually possible travel range even if they know the charge state of the battery at the time of starting travel. One approach to counter the range slope is to extend the range of the respective vehicle by increasing the available battery energy (i.e., in a "range increase"). However, there are limits to the increase in battery energy available per vehicle, since the progress in increasing practical energy density for large electric vehicle batteries is slow. Moreover, while hybrid electric vehicles are used to reduce range anxiety, higher costs are incurred when using combined electric drives with combustion propulsion systems; and at the same time, more extensive goals, such as reducing pollutant emissions and petroleum consumption to zero, are not met by using hybrid vehicles.BRIEF DESCRIPTION OF THE INVENTIONThe present invention provides a method of charging an electric vehicle having an electric battery as a vehicle drive system, the method comprising:charging the electric vehicle with a first electric current for a first period of time; andcharging the electric vehicle for a second period of time, which is shorter than the first period of time, with a second electric current, which is higher than the first electric current, wherein during the second charging process the supply of a coolant to the electric vehicle is provided in order to cool the electric battery for this second period of time.By virtue of this division into two separate charging processes, by virtue of the fact that the first charging period takes place, for example, overnight while the vehicle is standing in a garage, and the second charging period can also take place on the way at a high-performance charging station which is equipped for rapid charging and is publicly accessible and is situated on the road, it is possible to reduce the driving range.The various embodiments of the above-described method may have one or more of the following advantageous properties:The first charging period may be performed without supplying a coolant from the outside to the vehicle. The first charging period may be overnight. The first charging period may be performed using a standard 120 or 240 volt power supply to which the electric charger connected to the vehicle battery is connected. The electric vehicle can be operated exclusively electrically. The first electric current may be less than 10 kW and may be about 3 kW. The second electric current may be above 100 kW and may be 300 kW. The first charging period may be longer than 8 hours and may be, for example, about 12 hours. The second charging period may be shorter than one hour, and preferably less than 10 minutes, for example about 5 minutes. The second charging period can be designed such that the battery is not fully charged, but only up to a certain charging level, for example up to a capacity of 50% or, in a preferred variant, up to a capacity of more than 80%. The coolant can be supplied as a gas or as a liquid. The coolant can use the cooling system already present in the electric vehicle or can preferably comprise external cooling for the second charging period. This coolant may be an oil that is supplied to the battery at a rate of one liter per second or faster during the second cooling period. The coolant may be air supplied to the battery at a rate of 1,600 cubic feet (about 45 cubic meters) per minute or faster during the second cooling period. The coolant can be cooled by means of a cooling unit before being supplied to the battery.The present invention further provides a vehicle which can be electrically charged according to the method described above, and a vehicle charging station in the public space along the road, by means of which the electric vehicle can also be electrically charged on the road in the second charging period.The present invention also provides a method of charging an electric vehicle having an electric battery as a vehicle drive system, comprising:charging the electric battery using a charging station located along the road, wherein the charging process for cooling the electric battery comprises supplying a coolant to the electric vehicle during the charging.The present invention further provides a method for charging an electric vehicle having an electric battery as a vehicle drive system, comprising:charging the electric battery to a capacity of at least 50% within 10 minutes, wherein the charging process for cooling the electric battery comprises supplying a coolant to the electric vehicle during the charging.The present invention further provides a method for charging an electric vehicle having an electric battery as a vehicle drive system, comprising:charging the electric battery at 100 kW or more, wherein the charging process for cooling the electric battery includes supplying a coolant to the electric vehicle during charging.BRIEF DESCRIPTION OF THE DRAWINGSThe present invention is explained in more detail below with reference to the attached figures, wherein the figures show as follows: FIG. 1 ashows a schematic view of a charging system for an electric vehicle battery in an embodiment variant of the present invention; FIG. 1 b shows an alternative embodiment of an electric vehicle that may be used in connection with the charging system for an electric vehicle battery according to the present invention; FIG. 2 is a schematic view showing a variant embodiment of an electric vehicle battery for charging according to the present invention; andThe graph in FIG. 3 shows two curves in which the battery temperature is plotted against the charging time during rapid charging for a battery having three cells and a charging rate of 20 minutes.DETAILED DESCRIPTIONSince, on the one hand, it is difficult to predict the range of an electric vehicle accurately and, on the other hand, only slow advances are made in the field of increasing the practical energy density in large electric vehicle batteries, a further possibility for increasing the acceptance of purely electrically operated vehicles is seen in providing more fast charging columns along roads in the public space. In this context, when the phrase "along roads" is used, it is meant any location that is generally accessible by the vehicle from a public road. Thus, according to this definition, for example, all gas stations which are generally publicly accessible have their location along a road. As such, although regular nocturnal charging operations cannot mitigate range anxiety because they do not increase the range of a moving vehicle on the way, combined with the dismantling of the infrastructure of fast charging stations along roads, the ease of use and attractiveness of purely electrically powered vehicles can be increased. Increased acceptance for electric vehicles may result in mass-produced scale effects, and thus, in significant cost reductions in the vehicles themselves, and in conjunction therewith, lower cost of energy consumption in charging the batteries, which may result in electric vehicles becoming significantly less expensive than vehicles with conventional internal combustion engines or hybrid electric vehicles.The embodiments of the present invention provide high-power DC fast-charging stations along roads, wherein the fast-charging station can deliver up to 300 kW per electric vehicle or more (for example, to charge an electric vehicle battery of 30 kWh in 6 minutes), and wherein a coolant is provided together with the charging process for cooling the electric vehicle battery in order to prevent overheating of the battery during charging (for example, up to about 50 kW of heat can be generated by expectation during a 6 minute charging process). Conventional cooling methods providing external cooling, such as cooling the surfaces or the external surfaces of high voltage batteries, are not suitable for effectively reducing the heat generated by fast charging stations when charging up to 300 kW or more per electric vehicle. This is because the heat is generated during the charging process primarily within the electric vehicle battery, which not only makes cooling from the outside inefficient, but also leads to high temperature gradients occurring within the cell stack of the battery, which can cause damage to the battery and premature battery failure, which in turn raises the costs and increases the risk of dangerous thermal instability.Embodiments of the present invention can furthermore provide an efficient and secure method for internally cooling the cell stack-the so-called battery stack-at high charging rates, and they can provide a unique, highly effective, universally usable thermal management system. In addition, both the coolant and an optionally used heat exchanger do not have to be carried along in the vehicle, but are provided externally for the purpose of the charging process, which has the effect that only minimal additional weight is added by the variant embodiments according to the invention and the additional space requirement in the electric vehicle is likewise kept low. In contrast to electric vehicles having an exclusively in-vehicle cooling system, a coolant supply from the outside and an external heat exchanger can thus contribute to increasing the range of the electric vehicle and thus also reducing the range anxiety.Advantageously, an existing internal cooling system can be modified such that it can be connected to the external coolant supply of the charging stations according to the invention.FIG. 1 ashows a schematic view of a charging system 10 for an electric vehicle battery in an embodiment variant according to the invention. The charging system 10 comprises an electric vehicle 20. In an alternative embodiment, the electric vehicle 20 may be a hybrid electric vehicle additionally equipped with an internal combustion engine such that the vehicle operates with the engine in combination with the electric vehicle battery 30.An exemplary embodiment of the electric vehicle battery 30 according to the invention is explained in more detail with reference to FIG. 2. The electric vehicle battery 30 may be a modular battery having a plurality of battery cells 32 separated by a plurality of internal channels 34 extending within the battery 30 between the cells 32. The channels 34 are preferably provided at least in part with porous, compressible interconnects 36 which serve to establish an electrically conductive connection between adjacent cells 32 and which simultaneously allow the coolant to pass through the internal channels 34 between the cells 32 during the charging operation to cool the cells 32. In preferred embodiments, the electric vehicle battery 30 is the battery disclosed in US 2009 / 0239130 A1, which is hereby incorporated by reference into the present application, wherein the interconnectors 36 and the battery cells 32 are each formed in the same manner as the interconnectors and the planar cell modules disclosed in US 2009 / 0239130 A1. Each cell 32 includes a positive and a negative electrode, the positive electrode connecting to a positive terminal 39 and the negative electrode connecting to a negative terminal 40.The compressible interconnects 36 may be made of any type of material, such as a wire mesh, a compressible elastomeric matrix of metal or carbon fibers, or a conductive mat, that is sufficiently suitable and that meets the requirement to form a compressible, flexible, electrically conductive connection between adjacent surfaces of cell plate modules while maintaining sufficient clearance to allow the coolant to pass through the internal channels 34 to cool the cells 32 during the charging process. In the illustrative example in FIG. 2, six cells 32 arranged in a stack are illustrated within a housing 25 which has a rectangular cross section in this embodiment variant. The six cells 32 shown are an exemplary illustration of the battery 30, which, however, may also comprise dozens or hundreds of interconnected cells and thus form a very high voltage battery stack. The housing 25 comprises inlets and outlets through which the coolant can be passed through the internal channels 34, wherein the inlets and outlets can be automatically opened or closed.According to other preferred embodiments, the interconnects 36 may alternatively consist of a non-electrically and / or thermally conductive material and thus be provided merely as spacers between the cells 32 in order to thus form the channels 34 between the cells 32. In such embodiments, the cells 32 may be formed as insulating pockets provided with electrically conductive taps at the ends that allow the coolant to cool the cells 32 while passing through the channels 34 formed by interconnects 36.The terminals 39, 40 form the internal connection to the ends of the stack or stack of battery cell modules, wherein an internal current bus 28 serves as a connection to the positive terminal 39 and either the electrically conductive housing 25 serves as a negative current bus 29 to the negative terminal 40 or an additional negative current bus to the negative terminal 40 is provided. To monitor the cell voltage and cell temperature, the housing 25 can each comprise external, multipolar plug connections 37, 38 which are conductively connected via sense lines to electrical passages 35. A set of multipolar plug connectors 37, 38 can be provided for each cell 32. In order to provide data on the cell voltage and cell temperature for controlling the charging process of the battery 30, the multipolar plug connectors 37, 38 can be designed such that they transmit the determined voltage and temperature measurement values to the control unit 28 (see FIG. 1 a).Referring back to FIG. 1 a, a control unit 28 may be coupled to the electric vehicle battery 30, which control unit detects the status of the battery 30 and correspondingly controls the charging process of the battery 30. In order to be able to charge the battery 30 during a prolonged period of time during which the vehicle is not used, it may be possible to connect the battery 30 to a charger 44, the charger 44 being connected by means of a plug cable 54 to an electrical output 56, for example a standard socket with 120 or 240 volts alternating current. To enable full or partial charging of the electric vehicle battery 30, the outlet 56 may be located in a garage 52 of a residence 50 or any other type of accommodation, or may be provided at a commercial provider for overnight charging. For full or partial charging of the electric vehicle battery 30, the charger 44 and the battery 30 may be detachably coupled to an electrical line 24 arranged in the vehicle 20 connected to the terminals 39, 40 (see FIG. 2 ) by means of a charging cord 46. Due to the limited possible battery charge rate when charging the battery 30 via the electrical output 56 and the charger 44, it is not necessary to supply an additional coolant from the outside to the battery 30 during the overnight charging process at the output 56.Referring now to FIG. 1 b, an alternative embodiment of an electric vehicle 20' is shown that may be used in conjunction with the battery charging system 10 for electric vehicle batteries according to the present invention. The electric vehicle 20' has the same configuration as the electric vehicle 20 in FIG. 1 a, with the difference that the charging cord 46 in the electric vehicle 20' that is detachably coupled to the electric line 24 is inserted into a separate receptacle 122, which is coupled to the connections 39, 40 (see FIG. 2 ) via an electric line 124.The charger 44 may be, for example, a 3 kW charger that can fully charge a fully discharged electric vehicle battery 30 in an embodiment of 600 V, 40 Ah, 24 kWh according to the invention over a period of about eight hours. A vehicle 20 with an electric vehicle battery 30 in the described embodiment of 600 V, 40 Ah, 24 kWh can, under favorable conditions, realize approximately 4 miles (approximately 6.44 km) per kWh and a range of approximately 96 miles (approximately 154 km). If trips exceed this distance, further charging processes could be required for the electric vehicle battery 30 given the battery usage duration limited in this way. The driver of the vehicle 20 would have to charge the battery 30 intermittently on days when distances other than 96 miles (about 154 km) are covered.In order to be able to intermittently charge the electric vehicle battery 30 rapidly outside of the nocturnal or other usual charging operations, quick charging stations 60 should be positioned at strategic locations along public roads 80 to allow trips to be made with vehicle 20 if these trips may exceed the range of the battery 30. In a preferred embodiment, these fast charging stations 60 correspond, for example, to those fast charging stations disclosed in the same inventor's co-pending patent application under attorney docket number 617.1009 (US 2012 / 0043935 A1) and entitled STATION FOR RAPIDLY CHARGING AN ELECTRIC VEHICLE BATTERY (CHARGING STATION FOR FAST CHARGING AN ELECTRIC VEHICLE BATTERY), the entire disclosure of which is hereby incorporated by reference into the present application. For example, the vehicle 20 may have similar characteristics to those vehicles disclosed in co-pending co-inventor patent application under attorney docket number 617.1009 (US 2012 / 0043935 A1) and entitled STATION FOR RAPIDLY CHARGING AN ELECTRIC VEHICLE BATTERY (CHARGING STATION FOR RAPIDLY CHARGING AN ELECTRIC VEHICLE BATTERY) and / or co-pending co-pending co-inventor patent application under attorney docket number 617.1010 (US 2018 / 0013180 A1) and entitled RAPID CHARGING ELECTRIC VEHICLE AND METHOD AND APPARATUS FOR RAPID CHARGING (RAPIDLY CHARGEABLE ELECTRIC VEHICLE AND METHOD AND APPARATUS FOR RAPID CHARGING), the entire disclosure of which is hereby incorporated by reference into the present application.The fast charging station 60 may include a high-power charging source 62, in a preferred embodiment a high-power DC power source, for fast charging the battery 30 of the electric vehicle 20, and a coolant source 64 for introducing coolant into the battery 30 via the internal channels 34 (see FIG. 2 ) during the spark charging operation of the battery 30 at the high-power charging source 62. In preferred embodiments, the high power charging source 62 may be a high rate discharge battery or supercapacitor with the capability of charging at night or low rate power, as not only is it less expensive, but may also be provided less prone to failure. The operator of the vehicle 20 can start each of the quick charging stations 60 (only one of which is explained in more detail for clarity in FIG. 1 a), switch off the vehicle 20 and insert a connection 68 con an end of a feed 68 of the quick charging station 60 into a corresponding receptacle, which is accessible from outside the vehicle 20, into the vehicle 20. In the embodiment shown in FIG. 1 a, the feeder 68 leads out of a base region 72 of the fast charging station 60 and comprises a cable 68 awhich is coupled to a high-capacity charging source 62 and a hose 68 bwhich is coupled to a coolant source 64. The connector 68 cmay be inserted into the receptacle in the vehicle 20 such that the connector 68 cis temporarily engaged with the receptacle. The operator of the vehicle 20 may then operate a power switch that may be mounted on either the terminal 68 cor the base portion 72 of the quick charging station 60 to thereby initiate charging of the electric vehicle battery 30 at the quick charging station 60. After the current switch of the fast charging station 60 is actuated, it supplies the electric vehicle battery 30 with current from the high-capacity charging source 62 and with coolant from the coolant source 64 until the battery 30 is sufficiently charged. In a preferred embodiment of the present invention, the fast charging station 60 supplies the vehicle 20 with up to 300 kW and can correspondingly charge an embodiment of the battery 30 according to the invention with 600 volts, 30 kWh in approximately 6 minutes. During the about 6 minute rapid charging operation for the 30 kWh configuration of the battery 30, about 50 kW of heat may be generated in the cells 32 of the 30 kWh configuration of the battery 30. Without coolant, which is preferably provided during such a rapid charging process within the 30-kWh design of the battery 30 according to the invention, the battery 30 could be permanently damaged or destroyed by an undesired temperature increase. However, if sufficient coolant can be pumped from the coolant source 64 into the battery 30 through the supply 68 and the coolant line 26 while the battery 30 is supplied with power from the high-capacity charging source 62 via the supply 68 and the electric line 24, a part of the heat generated inside the battery 30 can be absorbed by the coolant and accordingly the battery 30 can be prevented from being damaged or destroyed during the charging process.In an alternative embodiment variant, which is used in particular when the coolant provided by the coolant source 64 is oil or another liquid, but potentially also when the coolant provided is air or another gas, a return line can be provided at the output ends of the channels 34 in the vehicle 20 in order to be able to return the coolant which has been conducted through the battery 30 to the coolant source 64 through the supply 68. In this alternative embodiment, an additional return hose, either integrated into the supply 68 or independent of the supply 68, may also be provided between the electric vehicle 20 and the fast charging station 60 to return the coolant to the coolant source 64. The fast charging station 60 may in that case be further equipped with a heat exchanger for removing the energy generated within the battery 30 from the recycled coolant.In another embodiment according to the invention, the vehicle 20 can also receive the current from the high-capacity charging source 62 and the coolant from the coolant source 64 separately at the fast charging station 60 instead of from a single feed 68, so that two feeds which are independent of one another can be provided between the fast charging station 60 and the vehicle 20. Thus, the two independent supplies can be, for example, on the one hand a cable coupled to the high-capacity charging source 62, which cable establishes a separable connection to an electrical receptacle coupled to the electrical line 24 by means of a connecting plug, and on the other hand a hose coupled to a coolant source 64, which hose establishes a separable connection to a coolant receptacle coupled to the coolant line 26 by means of a connecting piece. In further embodiments of the present invention, it is possible that a supply is used exclusively for the coolant source 64, while the high-capacity charging source 62 wirelessly charges the battery 30 in a charging process by induction or by magnetic resonance. Another alternative embodiment may provide a separate coolant return which is connected to a heat exchanger in the fast charging station 60.For the purpose of monitoring the amount of charge supplied from the high-capacity charging source 62 to the battery 30 and for monitoring the amount of coolant supplied from the coolant source 64 to the battery 30, and in embodiments which provide coolant recycling, also the amount of coolant fed back into the coolant source 64, a control unit 70 can be provided in the rapid charging station 60. While the vehicle 20 is connected to the quick charging station 60 for charging the battery 30, communication may be established between the control unit 70 and the control unit 28 of the battery 30 such that the control unit 70 may control the supply of charge from the high-capacity charging source 62 and the supply of coolant from the coolant source 64 according to the current state of the battery 30, respectively. For example, if the battery 30 is warmer or colder than usual (measured, for example, via connections 37, 38 as shown in FIG. 2 ) due to the existing weather conditions or the driving style that the vehicle 20 was previously driven, the supply rate and / or temperature of the coolant supplied from the coolant source 64 may be correspondingly regulated down or up. If the battery 30 is still partially charged and only needs to be charged by a small amount, the controller 70 may also limit the supply of charge from the high-capacity charging source 62 to a charge rate below the maximum charge rate and regulate the inflow rate and / or temperature of the coolant from the coolant source 64 to a corresponding value. The control unit 70 may comprise a memory correlating the amount of coolant to be supplied to the charge supplied and optionally also to the temperature of the battery 30. The control unit 70 may also provide information to an operator of the charging station 60 located along a road to the vehicle owner for billing purposes, for example, by calculating the charge provided and the price to be charged for the charging operation at the charging station 60. Further, the control unit 28 may transmit data regarding the current chemical state of the battery 30 measured at the battery 30 to the control unit 70, so that the control unit 70 may control the charging and cooling of the battery 30 and enable the safest method for charging the battery 30 based on the chemical data of the battery 30. An older battery 30, for example, which may be more compatible with a slower charging rate or which has a slightly different chemical state, may be charged from the fast charging station 60 to the charging and cooling rates defined according to these chemical data and stored in the control unit 70.In one embodiment, the battery 30 is a 100 kg 300 volt electric battery that can fully charge the electric vehicle 20 at 30 kWh. In this example, the battery 30, which includes one hundred cells 32 each at 3 volts and a resistance each of 1 milliohm, reaches its full charge at the high power charge source 62 at 180 kW after ten minutes. During charging, about 36 kW of heat is generated (about 6 kWh) in 10 minutes. To sufficiently cool the battery 30 during this charging operation to maintain an acceptable battery temperature of about 45 degrees Celsius, the coolant source 64 may provide oil (supplied at a temperature of 20 degrees Celsius) at a rate of at least 0.73 liters per second (44 liters per minute) or air (supplied at a temperature of 0 degrees Celsius) at a rate of at least 1,800 cubic feet (about 50.9 cubic metres) per minute. Charging and discharging rates of electric batteries are specified in industry-standard terms by the so-called C factor (C stands for "capacity" or capacity of the battery), the quotient of current and battery capacity. Regardless of the size of an electric battery, a charging current of 1 C or a discharging current of 1 C indicates that the battery is completely charged or discharged within one hour. A C factor of C / 8 means that charging or discharging takes eight hours each, and at 2 C, charging or discharging takes half an hour each. Accordingly, the C factor of the ten-minute charging battery 30 of the above-mentioned Example is 6 C.For example, to charge a battery 30 according to the present invention at 600 volts, 24 kWh within six minutes, it is possible to employ a 240 kW charger that provides 400 amps at 600 volts (DC) over six minutes as the high power charging source 62. The energy to be supplied can also be substantially higher due to considerable heat losses than if the charging process is completely efficient. For example, if there were two hundred cells of 3 volts each and 1 milliohm each, 32 kW of heat could be generated, requiring one minute for the charging process (about seven minutes in total).One embodiment of the present invention contemplates that the battery 30 is not fully charged to 100% of its charge capacity by the high capacity charge source 62, but instead is charged to 80% of its battery charge capacity within about 5 minutes by the high capacity charge source 62. By doing so to charge the battery 30 to 80% charge capacity, over-voltages can be avoided in some cells of the battery 30. If desired, then after 80% of the charge capacity of the battery 30 is reached, the charging operation may be continued with a reduction in the current supplied by the charge source 62 to charge the battery 30 by more than 80% of the charge capacity. If a completely discharged embodiment of the battery 30 according to the invention is recharged with 600 volts, 24 kWh and with two hundred cells each of 3 volts and a resistance of 1 milliohm again to 80% of the charging capacity (19.2 kWh) in five minutes, 2.7 kWh of heat (32 kW is generated in the battery 30 over five minutes corresponding to approximately 10 7 joules). To be able to remove this 2.7 kWh of heat in five minutes to a sufficient extent, oil may be at a rate of at least 40 liters per minute or air may be at a rate of at least 1,600 cubic feet (about. 45.3 cubic meters) per minute are routed through the interior of the battery 30 via the internal channels 34. The delayed heat transfer to the coolant associated therewith is counteracted in preferred embodiments of the present invention by passing the oil or air through the battery 30 at higher rates than at least necessary. In such embodiments, in the 600 volt battery described above, the oil may be directed at about 50 to 200 liters per minute or the air may be directed at about 2,000 to 8,000 cubic feet (about 56.6 to about 226.5 cubic meters) per minute through the interior of the battery 30 via the internal passages 34. The cooling rates may be proportionately higher or lower for larger or smaller batteries, respectively.Other embodiments of the present invention may include a cooling unit 66 for additionally cooling the air or oil used to cool the battery 30. The cooling unit 66 can be particularly advantageously used to cool cooling air by thus allowing the air to pass through the interior of the battery 30 at lower rates than about 2,000 to 8,000 cubic feet (about 56.6 to about 226.5 cubic meters) per minute via the internal channels 34.After charging the battery 30 via the fast charging station 60, the battery 30 may be internally air cooled or heated by passing air through the interconnectors 36. The air can be introduced as supply air via a full air conditioning system present in the vehicle 20 for heating, cooling and ventilation by means of the ventilation function. Thus, it is advantageous, for example on cold days in winter months, to ensure efficient and rapid warming of the battery by means of the heating together with the ventilation function, since otherwise the battery capacity losses are considerable (which in turn also reduces the range) at low temperatures. While the battery then heats up to the normal operating temperature, the waste heat that may be produced (for example by means of a small heat pump) can be used for heating or cooling the interior space-as a result of which, in addition, excess energy is not wasted in unused form but rather is used (and therefore the range of the vehicle 20 is extended further)-and can be used for regulating the rising temperature of the battery 30 in the event of transients caused by acceleration or braking. An alternative embodiment variant can provide that the battery 30 is liquid-cooled or liquid-heated in the interior after the charging process at the rapid charging station 60 by liquid being conducted through the interconnectors 36 by a liquid heat exchanger present in the vehicle 20, wherein the liquid heat exchanger is in turn cooled or heated up by a cooling or heating system present in the vehicle 20, and wherein this cooling or heating system can likewise serve to control the cooling and heating of the vehicle interior.In one embodiment of the present invention, the coolant line 26-and, if provided, the return line for the coolant-may be integrated into the full air conditioner of the electric vehicle 20. Accordingly, it is possible to utilize the coolant line 26 and the coolant return line for both thermal management of the battery 30 while the vehicle 20 is operating - in that the coolant line 26 and the coolant return line may serve to pass the coolant through the channels 34 (see FIG. 2 ) - and then during the fast charging operation to cool the battery 30 to pass the coolant provided by the fast charging station 60 through the channels 34. In order to couple the refrigerant line 26 and the return line to the supply line 68 alternately during travel with the full air conditioner and during charging, changeover valves may be provided.In addition, it is possible, for example, to convert the thermal energy dissipated from the battery 30 by means of the coolant conducted through into electrical energy either in the vehicle 20 or in the rapid charging station 60. For example, energy contained in the coolant may be recovered downstream from the battery 30 by coupling a turbine device or thermoelectric device in the vehicle 20 or in the vehicle 20' or in the fast charging station 60 or the fast charging station 60' to the outputs of the channels 34.In preferred embodiments, the battery 30 comprises nanoscale particles which in principle enable high charging rates. The nano-scale particles can be provided with a thin carbon layer. For example, the anodes of the cells 32 may be formed of lithium titanium oxide (LTO) nanoparticles and the cathodes may be formed of lithium iron phosphate (LFP) nanoparticles such that the battery 30 may be rapidly charged at a rate of up to 3 minutes (corresponding to a C factor of 20 C) and may also undergo many thousands of chargings without requiring the battery 30 to be replaced during the life of the vehicle 20 or 20'. For example, using such nanoparticles in the battery 30 in combination with the present invention limiting the temperature rise of the battery 30, it may be possible to charge the battery 30 more than 10,000 times. Assuming a range of 100 miles (about 160.9 km) per charging operation, the battery 30 could thus theoretically travel over 1,000,000 miles (about 1,609,344 km) during its lifetime. Such a long-lived battery 30 would have a high residual value and could be used again in another vehicle, for example. Furthermore, ecological and strategic advantages would be of concern for the United States, since the need for raw materials for the production of batteries would be reduced and fewer of the required raw materials would have to be imported.Refrigerants other than air or oil may also be provided by the refrigerant source 64. These can be, for example, flowable liquid or gaseous substances with an optimum heat capacity. In order to increase the heat exchange capacity, additives may be added to the coolant. In a preferred embodiment of the present invention, the coolant has electrically insulating properties.It is also possible to employ embodiments of the present invention in hybrid electric vehicles, as well as in other applications where large batteries are needed and for which fast charging with additionally supplied vehicle-external cooling may be advantageous. For example, fast charging stations could be used for charging and cooling trains, airplanes, military vehicles including weapon and combat applications such as large robots, tanks, drones, M777 Haubitzers, and railguns, etc., all of which would benefit from the ability to quickly charge the battery, and the amount of coolant needed and to be supplied would be proportional to the size of the battery and the desired charging speed. As used herein, the term "vehicle" is used to include any type of broadly mechanical devices and devices.In particular for military purposes, it may be useful in further embodiments to provide the fast charging stations 60, 60' as mobile charging stations, which can be transported from location to location there, where no stationary charging stations are available. Accordingly, the quick-charging stations may be integrated into a vehicle, for example into an armor vehicle, an aircraft or a truck, or they may be designed such that they can be loaded onto a vehicle for transport purposes or otherwise transported by a vehicle.The graph in FIG. 3 shows two curves in which the battery core temperature is plotted against the charging time during rapid charging for a battery having three cells and a charging rate of 20 minutes (i.e. a C factor of 3 C). The three-cell battery includes electrically conductive interconnects 36 (see FIG. 2 ) between the cells. Curve 200 plots the temperature of the three-cell battery as a function of the charging time without coolant inflow through the interconnectors 36, and curve 202 plots the temperature of the three-cell battery as a function of the charging time when coolant is introduced through the interconnectors 36 into the battery 30 at a speed of one liter per minute. In the underlying experiment, a commercially available heat transfer fluid was used, the thermal oil Paratherm LR, which is a paraffin-containing hydrocarbon with a broad spectrum of use between -50 and 230 degrees Celsius. Paratherm LR is characterized by a resistivity of about 10E14 ohm cm and a dielectric breakdown voltage (according to ASTM standard D1816-04, 0.1 inch / about 0.254 cm gap) of over 22 kV, which in the experiment was sufficient to protect the electrical battery components from damage caused, for example, by a short circuit that would also result in insufficient battery charge. The graph illustrates how the supply of coolant to a battery limits the increase in battery temperature. Without cooling, according to FIG. 3, the battery temperature rises from an initial temperature of 22 degrees Celsius in a charging process from 4 minutes to approximately 30 degrees Celsius and in 11 minutes to approximately 39 degrees Celsius. In comparison, the battery temperature only reaches 30 degrees Celsius after 11 minutes when coolant is conducted through the battery during charging. The temperature rise in the battery with the addition of coolant (difference of 8 degrees Celsius from the starting temperature) is correspondingly less than half as high as without coolant (difference of 17 degrees Celsius from the starting temperature). Further properties of the thermal oil Paratherm LR are listed in the following table.Maximum recommended film temperature500 oF / 260 OCMaximum recommended operating temperature450 oF / 232 OCMinimum operating temperature 20 cP (20 mPa*s)-58 oF / -50 OCMinimum starting temperature 300 cP (300 mPa*s)-112 oF / -80 OCKinematic viscosity at 60° F. / 15.5° C. cSt (mm 2 / s)2,4Density at 60° F. / 15.5° C. Ib / gal (kg / m 3)6,4 (766)Flash point (closed cup, D56)>130 oF / 54 OCIgnition temperature (maximum 10 s ignition delay)>500 oF / 260 OCBoiling point (14.7 psia / 101 kPa)397 oF / 202 OCVapor pressure @ maximum operating temperature psia (kPa)21 (145)% Thermal expansion over recommended operating temperature per 100 oF (OC)6,8 (12,2)Average molecular weight160Dielectric breakdown voltage D1816-04 (kV, 0.1 inch / about 0.254 cm gap)22,15Dielectric constant (1 kHz) D924-042,03Dielectric loss factor (1 kHz) D924-040,00001Resistivity at 100 V (Ω*cm) D257-071,84*10 14Calorific value (approximately) Btu / lb (kJ / kg)20.000 (46.300)Evaporation energy (approximately) Btu / lb (kJ / kg)113 (262)The invention has been described in the foregoing embodiments with reference to specific embodiments and examples thereof. It is, however, to be clearly understood that modifications or changes may be made to the invention without departing from the scope of 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.

Claims

A method of charging an electric vehicle (20) having an electric battery (30) as a vehicle propulsion system, the method comprising: charging the electric vehicle (20) with a first electrical current at a standard 120 or 240 volt terminal (56) for a first period of time; charging the electric vehicle (20) for a second period of time, which is shorter than the first period of time, with a second electric current, which is higher than the first electric current, via a high-performance charging source (62), which is different from the standard connection (56), wherein during the second charging process the supply of a coolant to the electric vehicle (20) is provided in order to cool the electric battery (30) for this second period of time, wherein the electric battery (30) has a plurality of battery cells (32), which are separated by a plurality of internal channels (34) running between the battery cells (32), which channels (34) are provided at least in part with porous, compressible interconnects (36), and through which channels (34) the coolant is passed in order to cool the battery cells (32) in the second period of time.Method according to Claim 1, in which the first charging period takes place without external supply of coolant to the electric vehicle (20).The method of claim 1, wherein the first charging period occurs overnight.Method according to Claim 1, in which the electric vehicle (20) is a purely electrically operated vehicle.The method of claim 1, wherein the first electrical current is less than 10 kW.The method of claim 1, wherein the second electric current is greater than 100 kW.The method of claim 1, wherein the first charging period is at least 8 hours.The method of claim 1, wherein the second charging period is shorter than one hour.The method of claim 8, wherein the second charging period is less than 10 minutes.Method according to Claim 1, in which, in the first charging period, the electric battery (30) is charged to an extent of at least 50% of its capacity.Method according to Claim 1, in which a cooling system present in the electric vehicle (20) is used for the coolant.The method of claim 1, wherein the coolant is gaseous and is supplied at a rate of 100 cubic feet (about 2.8 cubic metres) per minute or faster.The method of claim 1, wherein the refrigerant is in liquid form and is supplied at a rate of 0.1 liter per second or more rapidly.Method according to Claim 1, in which the coolant is cooled down by means of a cooling unit before it is supplied to the electric battery (30).An electric vehicle (20) charged according to the method of claim 1.A charging station (60) which is set up along a public road and by means of which an electric vehicle (20) according to claim 15 can be charged in the second charging period.A method of charging an electric vehicle (20) having an electric battery (30) as a vehicle propulsion system, the method comprising: charging the electric battery (30) via a first electric line (124) of the electric vehicle (20); Charging of the electric battery using a charging station (60) situated along the road via a second electric line (24) of the electric vehicle (20), wherein the charging process for cooling the electric battery (30) during charging comprises the supply of a coolant to the electric vehicle (20), wherein the electric battery (30) has a plurality of battery cells (32) which are separated by a plurality of internal channels (34) running between the battery cells (32), wherein the channels (34) are provided at least partially with porous, compressible interconnects (36), and wherein the coolant for cooling the battery cells (32) is passed through the channels (34).A method of charging an electric vehicle (20) having an electric battery (30) as a vehicle propulsion system, the method comprising: charging the electric battery (30) via a first electric line (124) of the electric vehicle (20); charging the electric battery (30) to a capacity of at least 50% within 10 minutes via a second electric line (24) of the electric vehicle (20), wherein the charging process for cooling the electric battery (30) during charging comprises supplying a coolant to the electric vehicle (20), wherein the electric battery (30) has a plurality of battery cells (32) which are separated by a plurality of internal channels (34) running between the battery cells (32), wherein the channels (34) are provided at least partially with porous, compressible interconnects (36) and through which channels (34) the coolant is passed for cooling the battery cells (32).

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