Method for controlling secondary lithium metal battery to obtain reserve energy capacity and battery control system incorporating same

Abstract

Aspects of the present disclosure include a control system for controlling a secondary lithium metal battery and for controlling an electrical device powered at least in part by the secondary lithium metal battery, which makes it possible to retrieve backup energy stored in the lithium metal battery that is typically unavailable during normal operation. In some embodiments, the control system provides energy harvesting to the backup in response to an emergency event, such as the need for additional energy to power the electrical device to a safe location.

Description

[0001] This application is a divisional application. The application number of the original parent application is 202010136799.2, the application date is March 2, 2020, and the name of the invention is "Method for controlling a secondary lithium metal battery to obtain backup energy capacity and a battery control system combined with the method." Background Art

[0002] Secondary (also known as rechargeable) lithium metal batteries offer great promise for next generation energy storage devices due to the significantly higher energy density they provide. Unlike conventional lithium ion batteries, which contain a negative electrode (also known as a negative electrode) formed of an intercalation material such as graphite, the lithium metal battery negative electrode is formed of a thin sheet of lithium metal such as lithium metal coupled to a current collector. The intercalation negative electrode of a lithium ion battery only provides a main structure for lithium ions and does not contribute to energy storage. In contrast, the lithium metal battery negative electrode is partially formed of lithium metal, which contributes to energy storage, thereby significantly increasing volume energy density and weight energy density. Summary of the invention

[0003] In one embodiment, the present disclosure relates to a method for controlling a lithium metal battery having a lithium metal negative electrode and a positive electrode having an intercalation site, the lithium metal battery having a normal operating range between 100% state of charge (SOC) and 0% SOC, 0% SOC corresponding to a discharge condition in which substantially all of the positive electrode intercalation sites are saturated with lithium ions. The method includes: monitoring the operating conditions of the lithium metal battery when the lithium metal battery discharges energy; receiving a backup energy signal; and allowing the battery to enter the backup energy operating range and discharge the backup energy in response to the backup energy signal by allowing the battery to discharge energy below 0% SOC.

[0004] In another embodiment, the present disclosure relates to a method for operating a load. The method includes receiving a battery signal, the battery signal including operating condition information of a lithium metal battery for providing electrical energy to the load; determining whether a backup energy capacity of the battery is needed based on the battery signal; and sending a backup energy signal to the battery in response to determining that the backup energy capacity is needed; wherein the backup energy signal includes an instruction for allowing the voltage of the battery to drop below a normal operating range cutoff voltage.

[0005] In yet another embodiment, the present disclosure relates to a battery controller for controlling a lithium metal battery having a lithium metal negative electrode and a positive electrode having an intercalation site, the lithium metal battery having a normal operating range between 100% state of charge (SOC) and 0% SOC, 0% SOC corresponding to a discharge condition in which substantially all of the positive electrode intercalation sites are saturated with lithium ions. The battery controller includes a processor configured to be operably coupled to the lithium metal battery and configured to monitor the operating condition of the lithium metal battery when the lithium metal battery discharges energy; receive a backup energy signal; and in response to the backup energy signal, allow the battery to enter the backup energy operating range and discharge the backup energy by allowing the battery to discharge energy below 0% SOC. BRIEF DESCRIPTION OF THE DRAWINGS

[0006] For the purpose of illustrating the invention, the accompanying drawings show aspects of one or more embodiments of the invention. However, it should be understood that the invention is not limited to the precise methods and apparatus shown in the accompanying drawings, in which:

[0007] Figure 1 is a schematic diagram of an exemplary lithium metal battery, load, and control system according to the present disclosure;

[0008] Figure 2 yes Figure 1 A schematic diagram of an exemplary rechargeable lithium metal battery cell of a battery;

[0009] Figure 3 is used for Figure 1 An exemplary voltage discharge curve of a lithium metal battery;

[0010] Figure 4 is a flow chart of an exemplary method of controlling a lithium metal battery to obtain backup energy;

[0011] Figure 5 is a flow chart of an exemplary method of controlling a load powered by a lithium metal battery; and

[0012] Figure 6 is a schematic diagram of an exemplary computing system that can be used to implement aspects of the present disclosure. DETAILED DESCRIPTION

[0013] Aspects of the present disclosure include control systems for controlling secondary lithium metal batteries and for controlling electrical equipment that is at least partially powered by the secondary lithium metal batteries, which makes it possible to obtain excess or backup energy stored in the lithium metal batteries that is typically unavailable during normal operation. In certain embodiments, the control system provides access to backup energy in response to an emergency, such as when additional energy is needed to power electrical equipment for transportation to a safe location. In certain embodiments, the acquisition of additional energy damages the battery, such as reducing battery life. In certain embodiments, aspects of the present disclosure include a secondary lithium metal battery having a negative electrode designed and configured to provide backup energy.

[0014] Figure 1 is a schematic illustration of an exemplary system 100 made according to the present disclosure, including a lithium metal battery 102 operably connected to a load 104 to provide electrical energy to the load, and a battery controller 106 for controlling the battery. As described more below, the battery controller 106 can be configured to access the reserve energy capacity of the battery 102 that is normally not used or available during normal operation of the battery but can be selectively accessed when needed.

[0015] In the illustrated embodiment, the battery 102 includes a plurality of electrochemical cells 108a, 108b, ... 108n that can be connected in series or in parallel to generate electrical energy for the load 104. A voltage can be applied to the positive and negative electrodes of the battery cells 108 by creating a circuit 110 or electrical connection between the electrodes. The battery controller 106 can also be operably and / or communicatively coupled to the battery cell electrodes and is configured to receive a single battery cell voltage signal SV 电池单元 and battery voltage signal SV 电池To monitor the voltage on each battery cell 108 and the total voltage generated by the battery 102. The battery 102 also includes a current sensor 112 configured to generate a current signal SA, a pressure sensor 114 configured to generate a pressure signal SP, and a temperature sensor 116 configured to generate a temperature signal ST. The battery controller 106 is communicatively coupled to each of the current, pressure and temperature sensors 112, 114 and 116 to receive the generated signals SA, SP and ST to monitor the state of the battery 102 in real time. The pressure sensor 114 may include one or more sensors located throughout the battery 102 to directly or indirectly monitor the pressure generated within the battery 102 during use, for example, the pressure generated by lithium plating on the negative and / or positive electrodes of the battery cell 108 and / or the pressure generated by any gas generated in the battery cell during charging or discharging. In one embodiment, the pressure sensor 114 includes one or more strain gauges located, for example, between adjacent battery cells 108 and / or between a battery cell and an adjacent group or housing, for monitoring the force generated by the battery cell due to the expansion of the battery cell due to lithium plating or generated gas. The temperature sensor 116 may include one or more of any type of temperature sensor known in the art, such as one or more thermocouples or thermistors.

[0016] The battery controller 106 may include an analog / digital chip (A / D chip) 130 for converting analog signals such as one or more of the current, pressure and temperature signals SA, SP and / or ST into digital signals, one or more processors and / or microcontrollers 132 and a memory 134. The battery 102 or battery controller 106 may also include various other features and components known in the art but not shown, such as voltage converters and regulator circuits for maintaining safe levels of voltage and current; electrical connectors for allowing power and information to flow into and out of the battery, etc. The processor 132 may be configured with instructions for providing a battery charge state, instructions for estimating the current charge state of the battery, and instructions for storing data related to battery parameters in the memory 134 and also transmitting the battery parameters to other processors.

[0017] The processor 132 may be configured with instructions for monitoring overcharge (overvoltage), overdischarge (undervoltage), and excessive charge and discharge currents (overcurrent, short circuit). The processor 132 may also be configured with instructions for protecting the battery 102 from harmful overcharge or undercharge or overcurrent conditions, for example, by controlling the switch 140 (e.g., a MOSFET or other control device) to limit energy transfer or completely disconnect the battery 102 from the load 104 or charger.

[0018] In some embodiments, the processor 132 may be configured to monitor the voltage signal V during charging and discharging. 电池单元 、V 电池 To determine whether any individual battery cell 108 is in a potentially damaged state. For example, during charging, an individual battery cell 108 may reach or exceed a safe voltage level even if the total battery voltage V 电池 Similarly, during discharge, the voltage of a single battery cell 108 may drop below a minimum safety threshold V 截止 , even if the voltage of the total battery voltage is still above its minimum safety threshold. In such an event, the processor 132 can stop charging or discharging the battery 102 or the individual battery cells 108 when the processor detects a single battery cell voltage at an unexpected value. The processor 132 can also evaluate the relative voltage levels of adjacent battery cells 108 and redistribute charge between adjacent battery cells to mitigate the differences in battery cell voltages.

[0019] The battery controller 106 may also be communicatively coupled to the load 104 during discharge and / or to a charger (not shown) during charging. The battery controller 106 may provide a battery signal SB to the load 104, which may include any of a variety of historical and real-time battery parameter information, such as real-time values ​​of battery voltage, current, temperature, pressure, SOC, and depth of discharge (DOD). The load 104 may be configured to provide a reserve energy signal SRE to the battery controller 106 to instruct the battery controller to allow the battery 102 to continue discharging into the reserve energy portion of the stored energy of the battery cell 108. As described more below, the battery controller 106 may reduce or deactivate the minimum battery voltage V 截止 To allow for a lower than V 截止 Continued discharge of battery 102 may cause cell 108 to switch from a normal operating chemistry in which lithium ions from the negative electrode of the cell are received at the intercalation site of the adjacent positive electrode to a backup energy chemistry in which the potential at the positive electrode intercalation site continues to be produced by the cell after it is substantially full.

[0020] The load 104 can be any device that consumes electrical energy. Non-limiting examples are computing devices (mobile phones, tablet computers, laptops, etc.), and electric vehicles based on land, air, or water (e.g., bicycles, cars, motorcycles, manned or unmanned aircraft vehicles, ships, submarines, etc.). The load 104 can include an electric drive system that includes one or more electric motors 150 for powering one or more propulsion devices for providing maneuverability or directional control of the load, such as wheels, or water or air propellers, ailerons, rudders, elevators, stabilizers, etc. The load 104 can also include one or more sensors 154 for monitoring the real-time conditions of the load, such as compasses, GPS receivers, inertial measurement devices, altimeters, internal and ambient temperature sensors, anemometers, pitot tubes, speedometers, and motor condition sensors (e.g., motor voltage, current, temperature, etc.). The load 104 may also include a memory 156 configured to store data such as device parameters 158, which may include any specifications of the load 104 or battery 102, such as the weight and aerodynamic or hydrodynamic properties of the load. The memory 156 may also include one or more applications executable by the processor 160, such as a guidance and navigation application 162 for providing real-time position and trajectory information and for controlling the speed and position of the load.

[0021] The system 100 may further include a remote controller 170 for providing a remote control signal SRC to the battery 102 and the load 104 and for receiving a battery signal SB and a load signal SL from the battery and the load, through any wired or wireless communication known in the art. For example, each of the remote controller 170, the battery controller 106, and the load 104 may include one or more communication modules (not shown) configured for one or more wireless communication protocols.

[0022] Figure 2 An exemplary battery cell 108 of the battery 102 is illustrated. Figure 2 Only certain basic functional components of the battery cell 108 are shown. A practical implementation of the battery cell and / or battery 102 will typically be embodied using a wound or stacked configuration, including components not shown for ease of illustration. Figure 2 Other components shown in the figure, such as electrical terminals, seals, thermal breakdown layers and / or ventilation holes, etc.

[0023] In the illustrated embodiment, the battery cell 108 includes a spaced-apart positive electrode 204 and a negative electrode 208, and a pair of corresponding respective current collectors 204A, 208A. A porous dielectric separator 212 is located between the positive electrode 204 and the negative electrode 208 to electrically separate the positive electrode and the negative electrode but allow lithium ions and ions of the electrolyte 216 to flow therethrough. The porous dielectric separator 212 and / or one, the other, or both of the positive electrode 204 and the negative electrode 208 may also be impregnated with the electrolyte 216. The battery cell 108 includes a container 220 that accommodates the current collectors 204A, 208A, the positive electrode 204, the negative electrode 208, the porous dielectric separator 212, and the electrolyte 216.

[0024] The positive electrode 204 and the negative electrode 208 may include various structures and materials compatible with lithium metal ions and the electrolyte 216. Each of the current collectors 204A, 208A may be made of any suitable conductive material, such as copper or aluminum, or any combination thereof. The porous dielectric separator 212 may be made of any suitable porous dielectric material, such as a porous polymer, etc.

[0025] The positive electrode 204 can be formed of various materials, such as materials of the general formula LixMyOz, where M is a transition metal such as Co, Mn, Ni, V, Fe or Cr, and x, y, z are selected to meet valence requirements. In one or more embodiments, the positive electrode is selected from LiCoO 2 、Li(Ni 1 / 3 Mn 1 / 3 Co 1 / 3 ) 2 、Li(Ni 0.8 Co 0.15 Al 0.05 ) 2 、LiMn 2 O 4 、Li(Mn 1.5 Ni 0.5 ) 2 O 4 or a layered or spinel oxide material of the group consisting of lithium-rich forms thereof. In one or more embodiments, the positive electrode material is LiCoO 2 (charged to 4.4 V vs. Li metal), NCA or NCM (622, 811) (charged to 4.30 V vs. Li metal).

[0026] As described more below, in some embodiments, the positive electrode 204 is constructed from a material having a layered structure (e.g., LCO, NCM662, NCM811) that can be relatively easily changed to another structural type after all intercalation sites of the positive electrode material have been filled with lithium ions. For example, the layered structure of a high temperature LCO, such as the cubic spinel structure as opposed to the low temperature LCO. Exemplary positive electrode materials having a layered structure are described in Heike Gabrisch, Rachid Yazami, and Brent Fultz, "Hexagonal to cubic spinel transformation in lithiated cobaltoxide", Journal of The Electrochemical Society, 151 (6) A891-A897 (1084) (available at https: / / authors.library.caltech.edu / 3039 / 1 / GABjes04.pdf). The negative electrode 208 may be a thin lithium metal negative electrode having a thickness in the range of 10 μm-100 μm, or 20 μm-80 μm, or 40 μm-60 μm in a discharged state. Figure 2 The negative electrode 208 is schematically shown adjacent to the current collector 208a, but a sheet or film of negative electrode material, such as lithium metal, can be arranged on both sides of the current collector. Further information about exemplary materials and constructions of the battery cell 108 can be found in PCT Publication No. WO2017 / 214276, entitled "High energy density, high power density, high capacity, and room temperature capable 'anode-free' rechargeable batteries", which is incorporated herein by reference in its entirety.

[0027] Figure 3 An exemplary voltage discharge curve 300 is shown, showing the battery cell voltage V during battery cell discharge at an exemplary discharge rate. 电池单元 Compared to the depth of discharge (DOD) plot. DOD is defined as the upper voltage limit when the battery is fully charged. 上限 and a cutoff voltage V at which the battery controller 106 is configured to stop battery discharge to prevent damage to the battery cells. 截止 The percentage of the capacity of the battery 102 between V 截止 Thereafter, as the intercalation sites of the positive electrode become saturated, the voltage curve 300 drops sharply. 截止At V, the battery cell is considered fully discharged, as indicated by DOD = 100%, approximately 3 V in this embodiment. 上限 and V 截止 The battery cell voltage discharge curve 300 between V 上限 and V 截止 reversibly cycles between, wherein Li from the positive electrode 204 is plated on the negative electrode 208 during charging and Figure 3 During the discharge process shown in FIG, the plated Li is stripped from the negative electrode and inserted back into the positive electrode. The discharge process is generated in Figure 3 The potential plotted in FIG. 3 is relatively constant throughout the majority of the normal operating range 302 in which the negative electrode stripping and positive electrode intercalation reactions are in electrochemical equilibrium. 电池单元 drops below V 截止 Afterwards, V 电池单元 In the illustrated embodiment, the sharp drop is due to the positive electrode intercalation sites becoming full or saturated, which effectively leads to an increase in resistance, which leads to a sharp drop in voltage.

[0028] exist Figure 3 The exemplary voltage discharge curve 300 shown in FIG. 1 is for a constant current discharge of 1.7 A. The slope and shape of the voltage discharge versus energy level will vary with the discharge rate, with higher discharge rates resulting in a faster drop in the cell voltage and slower discharge rates resulting in a more gradual drop in the cell voltage. Thus, a continuous rapid discharge rate will result in the cell reaching V before 100% DOD. 截止 , and a more gradual rate will result in the cell voltage reaching the cut-off voltage V 截止 During normal operation of the battery 102, the battery controller 106 is configured to monitor the battery cell voltage, current and discharge rate and to initiate a charge when the battery cell voltage reaches V 截止 The battery 102 is disconnected or otherwise terminated when the discharge is stopped to prevent damage to the battery and to maximize the life of the battery. As mentioned above, in some embodiments, the battery controller 106 can be configured to monitor the battery cell voltage of each of the battery cells 108 and can be used when the battery cell voltage V 电池单元 drops below the cut-off voltage V 截止In other embodiments, the battery controller 106 may be configured to selectively stop the discharge of only one of the battery cells 108 that drops below their respective cutoff voltages but allow their voltage to remain above V 截止 The other battery cells 108 continue to discharge.

[0029] The characteristics of the discharge curve 300 in the normal operating range 302 are similar to those of a conventional lithium ion battery discharge curve. As with the lithium metal battery 102, during discharge of a conventional lithium ion battery, lithium ions continuously fill the positive electrode intercalation sites and the voltage curve suddenly drops when the positive electrode intercalation sites become saturated. However, in a lithium ion battery, when all of the positive electrode intercalation sites are substantially full, all of the negative electrode intercalation sites are substantially empty, meaning that there are no additional lithium ions available for continued energy extraction. Unlike conventional lithium ion batteries, the lithium metal battery 102 is designed and configured to operate in a backup energy operating range 304, in which the battery cell 108 is configured to be discharged when the battery cell voltage drops below the cutoff voltage V 截止 The potential is then continued to be generated, and discharge is continued after all positive intercalation sites are full and the cell voltage drops sharply. Figure 3 As shown in FIG. 1 , after the battery cell voltage drops sharply, the voltage stabilizes at a non-zero backup energy voltage V after passing through a transition point 306 between the normal operating range and the backup operating range 302 , 304 . 备用能量 , whereas the cell voltage of a conventional lithium-ion battery will simply continue to zero after reaching 100% DOD. After the transition point 306, the electrochemical process in the cell begins to shift from filling the positive electrode intercalation sites with stripped lithium ions from the negative electrode to one or more alternate energy chemical reactions that also generate electrical potential.

[0030] The battery cell 108 can be designed and configured for a variety of different backup energy chemistries and for varying amounts of backup energy. An embodiment of a backup energy chemical reaction includes a redox reaction between the stripped lithium ions and the electrolyte 216. For example, in the case of a carbonate electrolyte 216, such as one or more of ethylene carbonate (EC), propylene carbonate (PC), ethyl methyl carbonate (EMC), dimethyl carbonate (DMC), or diethyl carbonate (DEC), a redox reaction in the form of RO-CO-OR+Li+->LiOR+CO2+RH. Another embodiment of a backup energy reaction is a continued chemical reaction between the stripped lithium ions and the positive electrode 204, which in some embodiments results in a change in the phase composition of the positive electrode material, such as from a layered LiCoO 2 Change to cubic spinel Li 1+y Co 2 O4 In certain embodiments, the positive electrode 204 is designed and configured to maximize the reserve energy by being formed from a material that more easily reacts with lithium ions during the reserve energy chemical reaction. For example, the positive electrode 204 can be formed from a material having a crystal structure that provides a chemical reaction at a lower activation energy level. For example, the positive electrode 204 can be formed from a material having a layered structure, such as high temperature LCO, NCM532, NCM622, NCM811.

[0031] As in Figure 3 As shown in FIG. 3 , the discharge curve 300 is at the maximum reserve energy DOD DOD 最大备用能量 Again, a sharp drop occurs, at which one or more of the reactants of the reserve energy reaction is consumed. The battery cell 108 can be designed and configured such that the limiting reactant is the lithium metal on the negative electrode 208. For example, in the reserve energy operating range 304, excess lithium metal can continue to be stripped from the negative electrode after the intercalation sites of the positive electrode 204 are saturated, providing additional reserve energy, until all or substantially all of the lithium metal has been stripped from the negative electrode 208, leaving, for example, only the current collector 208a. In one embodiment, the volume of lithium metal located on the negative electrode 208 when the battery cell is in a discharged state is designed and configured to be a target amount for reserve energy. For example, the thickness of the lithium metal can be increased to increase the reserve energy capacity. In one embodiment, the relationship between the lithium metal thickness and reserve energy is that 1 μm of lithium metal is approximately equal to 1% additional energy. For Figure 3 In the illustrated embodiment, the battery cell has approximately 50% reserve energy discharge capacity, which in the illustrated embodiment corresponds to approximately an additional 20% reserve energy (due to the lower discharge voltage of 1.5V (energy = discharge capacity * voltage)), meaning an additional 50% of the normal operating mode discharge capacity (and an additional 20% of the normal operating mode energy), or approximately 150% DOD 最大备用能量 , and the lithium metal on the negative electrode 208 is approximately 20 μm in a normal fully discharged state (100% DOD). Therefore, in the illustrated embodiment, the DOD 最大备用能量 50% greater than DOD. In some embodiments, DOD 最大备用能量 can be at least 20% greater than the DOD, and in some embodiments, the DOD 最大备用能量 20% to 200% greater than DOD, and in some embodiments, DOD 最大备用能量 20% to 150% greater than DOD, and in some embodiments, DOD 最大备用能量 20% to 120% greater than DOD, and in some embodiments, DOD 最大备用能量 20% to 100% greater than DOD, and in some embodiments, DOD 最大备用能量20% to 80% greater than DOD, and in some embodiments, DOD 最大备用能量 20% to 60% greater than DOD, and in some embodiments, DOD 最大备用能量 20% to 40% greater than DOD. The electrolyte 216 and cathode 204 may also be designed and configured to be combined with a specific amount of excess lithium metal volume for backup energy. For example, the reduction potentials of ethylene carbonate (EC) and dimethyl carbonate (DMC) are 0.9 V and 1.32 V, respectively, compared to Li + / Li. Changing the carbonate type of the electrolyte (e.g. changing EC to DMC) will change the reduction potential of the electrolyte and, as a result, will change the reserve energy. In addition, increasing the electrolyte volume will increase the amount of reserve energy due to electrolyte reduction. Details of the phase composition changes of the cathode material (e.g. changing the layered LiCoO 2 Change to cubic spinel Li 1+y Co 2 O 4 ) will also affect the amount of available backup energy based on the negative to positive electrode ratio (N / P ratio). In one embodiment, the N / P ratio is 0.85-0.9 for a cell in a state of discharge with DOD=100%.

[0032] In some embodiments, the battery 102 may be configured to not normally capture the backup energy range 304 because the chemical reactions that occur within the battery cells 108 to capture the backup energy may not be as reversible as the chemical reactions that occur during the normal operating range 302. In some embodiments, if all or a portion of the backup energy range 304 is captured, then the life of the battery 102 may be reduced, and in some embodiments, significantly reduced. For example, in some embodiments, if all or substantially all of the backup energy range 304 is consumed, then the battery 102 may no longer be rechargeable and may need to be replaced. Therefore, during normal operation, the battery controller 106 may be configured to monitor the operating conditions of the battery 102 in real time and to detect when the battery cell voltage and / or battery voltage drops below the normal operating cut-off voltage V 截止 Or when the battery SOC or DOD reaches 0% or 100%, the battery discharge is stopped.

[0033] In some embodiments, the load 104 can be configured to obtain the reserve energy in the battery 102 by instructing the battery controller 106 to extend the operation into the reserve energy operation range 304. The load 104 can be configured to instruct the battery controller 106 to obtain the reserve energy range 304 through the reserve energy signal SRE, for example, by using a lower cut-off voltage instead of the normal operation cut-off voltage V 截止, ignoring the cutoff voltage, and / or using a DOD greater than 100% instead of a 100% target DOD. Figure 3 As shown in FIG. 1 , the battery controller 106 can be configured to ignore the cutoff voltage V 截止 and allow the battery cell voltage to continue to drop until there is no energy left to obtain backup energy, and / or V 截止 to a lower voltage, such as slightly less than V 备用能量 , or the expected or calculated voltage associated with completion of all reserve energy chemical reactions, such as approximately 1.3-1.4 volts in the illustrated embodiment, or until the calculated DOD reaches the expected maximum DOD, such as approximately 150%-160% in the illustrated embodiment. In some embodiments, one or both of memory 134 and memory 156 may store the DOD 最大备用能量 and / or V 备用能量 And the battery controller 106 can obtain the DOD 最大备用能量 and / or V 备用能量 Used to estimate the amount of reserve energy remaining and / or to determine when to stop discharging the battery.

[0034] In one embodiment, the guidance and navigation application 162 may include instructions for receiving real-time battery conditions, such as DOD, from the battery controller 106 and for continuously performing calculations to determine the amount of battery capacity required to return the load 104 to a safe location. For example, when the load 104 is an aircraft vehicle, the guidance and navigation application 162 may include instructions for determining the distance from a home base or other safe landing location and the amount of energy ERH required to return to the home base. The guidance and navigation application 162 may be configured to generate a user prompt or warning, such as an audible, visual, and / or tactile warning, through a user interface, such as a user interface incorporated into the remote controller 170, when the battery normal operating SOC begins to approach the ERH. For example, the application 162 may be configured to generate a user prompt or warning, such as an audible, visual, and / or tactile warning, when the battery normal operating SOC begins to approach the ERH. 充电状态≤ERH+T, where T is a threshold value, such as between 5% and 25% SOC. If the load 104 is in an unsafe location (e.g., the aircraft vehicle is still in the air) when the SOC of the battery 102 approaches 0%, the battery controller 106 may be configured to prompt the user to select a backup energy operating mode, and in response to the user selection of the backup energy operating mode, allow the battery to continue to discharge in the backup energy operating range 304. In other embodiments, the battery controller 106 and / or the guidance and navigation application 162 may be configured to automatically allow the battery to extend into the backup energy operating range 304 if the SOC approaches 0% and the vehicle is in an unsafe condition that could result in damage or loss of the vehicle if battery power was terminated.

[0035] After entering the backup energy operating range 304, the battery controller 106 may continue to monitor the real-time condition of the battery and adjust the battery status when the battery DOD begins to approach the DOD 最大备用能量 In some embodiments, the guidance and navigation application 162 can be configured to switch to autopilot mode and automatically begin navigating the load to a safe location, such as GPS coordinates stored in the memory 156, after the battery enters the backup energy range 304 or when the DOD 最大备用能量 -DOD≤ERH+T, where T is a threshold value, for example between 5% and 25% SOC.

[0036] The guidance and navigation application 162 may calculate the ERH using any calculation technique known in the art that is suitable for a given load 104. For example, in the case of an aircraft vehicle, the guidance and navigation application 162 may be configured to receive the distance from the home base (or other safe location), the altitude above the home base, the energy efficient speed, and an estimate of the wind speed on track toward the home base based on the difference between the actual speed (m / s) and a known speed predicted based on, for example, the manufacturer's specifications, and may determine the ERH using one or more analytical techniques, such as application of the following four kinematic equations:

[0037] v=v o +at Equation (1)

[0038]

[0039] In one embodiment, the guidance and navigation application 162 may be configured to perform the following:

[0040] ERH=E trans -E 势能 Equation (5)

[0041] in:

[0042] E trans = 1 / 2 mv 2 +E 无效率 , where v and m are the speed and mass of the vehicle, respectively, and E 无效率 is the energy that is wasted through the inefficiency of staying aloft; and

[0043] Potential energy E due to height 势能 =mgh, where m is the mass of the vehicle and g is the acceleration due to gravity.

[0044] In one embodiment, the guidance and navigation application 162 may be configured to generate user prompts or warnings, such as audible, visual, and / or tactile warnings, through a user interface, such as a user interface incorporated into the remote controller 170, when the battery's normal operating SOC begins to approach the ERH. For example, the application 162 may be configured to 充电状态 ≤ERH+T, the user is instructed to return the aircraft vehicle to the home base, where T is a threshold, such as between 5% and 25% SOC.

[0045] Figure 4 An exemplary method for controlling a lithium metal battery is illustrated. Method 400 may be performed by a computing device, such as battery controller 106, that receives a battery operating condition, such as a battery voltage, and is configured to determine a real-time DOD or SOC of the battery and / or compare the voltage of the battery to a cutoff voltage. In box 401, the battery controller may provide battery information, such as a battery or battery cell voltage DOD and / or SOC, to a second computing device, such as a controller of a load powered by the battery, such as load 104. In box 403, in response to sending the battery information, the load and / or the operator of the load may send a backup energy instruction to allow the battery to continue to discharge energy and transition from a normal operating range, such as normal operating range 302, to a backup energy operating range, such as backup energy operating range 304. In box 405, in response to receiving the backup energy instruction, the battery controller may allow the battery to continue to discharge energy and transition to the backup energy operating range.

[0046] Figure 5An exemplary method for controlling an electrically powered load powered by a lithium metal battery is illustrated. Method 500 may be performed by a computing device, such as a processor 160 of a load 104. In box 501, the computing device may receive battery energy level information for a battery that is powering the load, such as from a battery or battery controller, such as battery controller 106. In box 503, the computing device may determine whether the load is in an unsafe location, such as a location where the load may be damaged if the battery power suddenly stops. As an example, if the load is an aircraft vehicle, the computing device may check one or more signals received from sensors 154 to determine whether the vehicle is currently in flight. In box 505, the computing device may send a backup energy command to the battery in response to determining that the battery energy level is approaching the end of the normal battery operating range and the vehicle is in an unsafe location, so that the battery will continue to provide power to the load by continuing to discharge power, even if the battery reaches the end of the normal operating range and 0% SOC. As mentioned above, in some embodiments, when the battery discharges the reserve energy and drops below 0% SOC, the battery may be damaged, for example, a reserve energy chemical reaction that may be irreversible may occur, which may result in a reduction in the life of the battery or an inability to recharge the battery. However, the computing device may be configured to send a reserve energy command to the battery to avoid damage to the load, even if this results in damage to the battery.

[0047] In box 507, the computing device may perform an energy calculation for transportation to a safe location to determine the amount of battery energy or power required to return the load to a safe location. In some embodiments, the computing device may continuously perform calculations based on real-time data from sensors such as sensor 154 to provide real-time energy values ​​for transportation to a safe location. In some embodiments, the computing device may continuously perform energy calculations for transportation to a safe location after the battery SOC reaches a minimum value, such as a value in the range of 10%-25%. In some embodiments, the computing device may continuously perform energy calculations for transportation to a safe location after sending a backup energy command signal because the battery is converting to backup energy and limited battery power remains. In box 509, the computing device may initialize autopilot operation to automatically return the vehicle to a safe location after determining that the amount of backup energy remaining is less than the determined energy for transportation to a safe location plus a threshold, where the threshold may be, for example, in the range of 0% to 25%, and in some embodiments, may be a value defined by the user.

[0048] Any one or more of the aspects and embodiments described herein can be conveniently implemented using one or more machines programmed according to the teachings of the present invention (e.g., one or more computing devices used as user computing devices for electronic files, one or more server devices, such as file servers, etc.), as will be apparent to those skilled in the computer arts. Suitable software coding can be easily prepared by skilled programmers based on the teachings of the present disclosure, as will be apparent to those skilled in the software arts. The aspects and implementations of the use of software and / or software modules discussed above may also include suitable hardware for the implementation of machine-executable instructions of the auxiliary software and / or software modules.

[0049] Such software can be a computer program product using a machine-readable storage medium. A machine-readable storage medium can be any medium capable of storing and / or encoding a sequence of instructions for being executed by a machine (e.g., a computing device) and causing the machine to execute any one of the methods and / or embodiments described herein. Embodiments of machine-readable storage media include, but are not limited to, disks, optical disks (e.g., CDs, CD-Rs, DVDs, DVD-Rs, etc.), magneto-optical disks, read-only memory "ROM" devices, random access memory "RAM" devices, magnetic cards, optical cards, solid-state memory devices, EPROMs, EEPROMs, and any combination thereof. Machine-readable media, as used herein, is intended to include a single medium and a collection of physically separated media, such as a collection of optical disks or one or more hard disk drives combined with a computer memory. As used herein, a machine-readable storage medium does not include signal transmission in an instantaneous form.

[0050] Such software may also include information (e.g., data) carried as a data signal on a data carrier, such as a carrier wave. For example, machine-executable information may be included as a data-bearing signal embodied in a data carrier, in which the signal encodes a sequence of instructions or a portion thereof for execution by a machine (e.g., a computing device) and any related information (e.g., data structures and data) that causes the machine to perform any of the methods and / or embodiments described herein.

[0051] Examples of computing devices include, but are not limited to, electronic book reading devices, computer workstations, terminal computers, server computers, handheld devices (e.g., tablet computers, mobile phones, etc.), network devices, network routers, network switches, network bridges, any machine capable of executing a sequence of instructions specifying actions to be taken by the machine, and any combination thereof. In one embodiment, the computing device may include and / or be included in a self-service terminal.

[0052] Figure 6A diagram of one embodiment of a computing device in the exemplary form of a computer system 600 is shown within which a control system such as Figure 1 A set of instructions may be executed by a battery control system and / or a load control system to perform any one or more of the aspects and / or methods of the present disclosure. It is also contemplated that multiple computing devices may be utilized to implement a set of instructions specifically configured to cause one or more of the devices to perform any one or more of the aspects and / or methods of the present disclosure. Computer system 600 includes processor 604 and memory 608, which communicate with each other and with other components via bus 612. Bus 612 may include any of a variety of types of bus structures, including but not limited to a memory bus, a memory controller, a peripheral bus, a local bus, and any combination thereof, using any of a variety of bus architectures.

[0053] The memory 608 may include various components (e.g., machine-readable media), including, but not limited to, random access memory components, read-only components, and any combination thereof. In one embodiment, a basic input / output system 616 (BIOS), including basic routines that help transfer information between elements within the computer system 600, such as during startup, may be stored in the memory 608. The memory 608 may also include (e.g., stored on one or more machine-readable media) instructions (e.g., software) 620 that embody any one or more of the aspects and / or methods of the present disclosure. In another embodiment, the memory 608 may also include any number of program modules, including, but not limited to, an operating system, one or more application programs, other program modules, program data, and any combination thereof.

[0054] The computer system 600 may also include a storage device 624. Embodiments of storage devices (e.g., storage device 624) include, but are not limited to, hard disk drives, disk drives, optical disk drives combined with optical media, solid-state memory devices, and any combination thereof. The storage device 624 may be connected to the bus 612 by a suitable interface (not shown). Exemplary interfaces include, but are not limited to, SCSI, Advanced Technology Attachment (ATA), Serial ATA, Universal Serial Bus (USB), IEEE 1394 (FIREWIRE), and any combination thereof. In one embodiment, the storage device 624 (or one or more components thereof) may be removably interfaced with the computer system 600 (e.g., via an external port connector (not shown)). In particular, the storage device 624 and associated machine-readable media 628 may provide non-volatile and / or volatile memory for machine-readable instructions, data structures, program modules, and / or other data for the computer system 600. In one embodiment, the software 620 may reside entirely or partially in the machine-readable medium 628. In another embodiment, the software 620 may reside entirely or partially in the processor 604.

[0055] The computer system 600 may also include an input device 632. In one embodiment, a user of the computer system 600 may enter commands and / or other information into the computer system 600 via the input device 632. Examples of the input device 632 include, but are not limited to, an alphanumeric input device (e.g., a keyboard), a pointing device, a joystick, a joystick, an audio input device (e.g., a microphone, a voice response system, etc.), a cursor control device (e.g., a mouse), a touch pad, an optical scanner, a video capture device (e.g., a still camera, a video camera), a touch screen, and any combination thereof. The input device 632 may be connected to the bus 612 via any of a variety of interfaces (not shown), including, but not limited to, a serial interface, a parallel interface, a game port, a USB interface, a FIREWIRE interface, a direct interface to the bus 612, and any combination thereof. The input device 632 may include a touch screen interface, which may be part of or separate from the display 636, discussed further below. The input device 632 may be utilized as a user selection device for selecting one or more graphical representations in a graphical interface, as described above.

[0056] The user can also enter commands and / or other information into the computer system 600 via a storage device 624 (e.g., a removable disk drive, a flash drive, etc.) and / or a network interface device 640. A network interface device such as the network interface device 640 can be used to connect the computer system 600 to one or more of a variety of networks, such as a network 644 and one or more remote devices 648 connected thereto. Embodiments of network interface devices include, but are not limited to, network interface cards (e.g., mobile network interface cards, LAN cards), modems, and any combination thereof. Embodiments of networks include, but are not limited to, wide area networks (e.g., the Internet, enterprise networks), local area networks (e.g., networks associated with offices, buildings, campuses, or other relatively small geographic spaces), telephone networks, data networks associated with telephone / voice providers (e.g., mobile communications provider data and / or voice networks), direct connections between two computing devices, and any combination thereof. Networks such as the network 644 can employ wired and / or wireless communication modes. In general, any network topology can be used. Information (eg, data, software 620 , etc.) may be communicated to and / or from computer system 600 via network interface device 640 .

[0057] The computer system 600 may also include a video display adapter 652 for communicating displayable images to a display device such as a display device 636. Embodiments of display devices include, but are not limited to, liquid crystal displays (LCDs), cathode ray tubes (CRTs), plasma displays, light emitting diode (LED) displays, and any combination thereof. Display adapter 652 and display device 636 may be used in combination with processor 604 to provide graphical representations of aspects of the present disclosure. In addition to the display device, the computer system 600 may include one or more other peripheral output devices, including but not limited to audio speakers, printers, and any combination thereof. Such peripheral output devices may be connected to bus 612 via peripheral interface 656. Embodiments of peripheral interfaces include, but are not limited to, serial ports, USB connections, FIREWIRE connections, parallel connections, and any combination thereof.

[0058] In certain embodiments, aspects of the present disclosure may further include a device of the present disclosure configured to receive electrical energy from a lithium metal battery. The device includes a processor configured to be operably coupled to the lithium metal battery and configured to receive a battery signal, the battery signal including operating condition information for the lithium metal battery; determine whether a backup energy capacity of the battery is needed based on the battery signal; and send a backup energy signal to the battery in response to determining that the backup energy capacity is needed; wherein the backup energy signal includes instructions for allowing the voltage of the battery to drop below a normal operating range cutoff voltage. Such an exemplary device may also include one or more of the following features: the battery signal includes information about the remaining amount of normal operating range energy stored in the battery; the determining step includes determining the likelihood that the load will be damaged if power from the battery is to be immediately stopped; the step of sending a backup energy signal includes instructing the battery to continue discharging energy after reaching a normal operating range state of charge of 0%; substantially all intercalation sites of one or more positive electrodes of the battery are substantially saturated when the battery reaches a normal operating range state of charge of 0%; the step of sending a backup energy signal includes instructing the battery to allow the voltage of the battery to drop to a backup energy voltage and to reach equilibrium at the backup energy voltage until substantially all of the backup energy capacity is discharged, the backup energy voltage being less than the normal operating range cutoff voltage; the step of sending a backup energy signal includes instructing the battery to be in a backup energy operating range in which substantially all intercalation sites of one or more positive electrodes of the battery are substantially saturated operating in a normal operating range; the reserve energy operating range is an operating range in which substantially all intercalation sites of one or more positive electrodes of the battery are substantially saturated; the reserve energy operating range is an operating range in which the potential is generated by a reserve energy chemical reaction, the reserve energy chemical reaction including at least one of a redox reaction between stripped lithium ions and the electrolyte of the battery and a chemical reaction between the stripped lithium ions and the positive electrode of the battery that causes a phase change of the positive electrode; the battery signal is an indication of a normal operating range energy level of the battery, and the processor is further configured to receive a reserve energy capacity value indicating a maximum amount of reserve energy; wherein the step of determining whether the reserve energy capacity of the battery is needed includes determining the amount of energy required to transport the load to a safe location; and automatically initializing an autopilot operation to autonomously transport the load to a safe location when the normal operating range energy level plus the reserve energy capacity is less than the determined amount of energy required to transport the load to a safe location plus a threshold.

[0059] In certain further embodiments, a machine-readable storage medium of the present disclosure may include machine-readable instructions for executing a method for controlling a lithium metal battery having a lithium metal negative electrode and a positive electrode having an intercalation site, the lithium metal battery having a normal operating range between 100% state of charge (SOC) and 0% SOC, 0% SOC corresponding to a discharge condition in which substantially all of the positive electrode intercalation sites are saturated with lithium ions, the machine-readable instructions including instructions for: monitoring the operating condition of the lithium metal battery while the lithium metal battery is discharging energy; receiving a backup energy signal; and in response to the backup energy signal, allowing the battery to enter the backup energy operating range and discharge the backup energy by allowing the battery to discharge energy below 0% SOC. Such an exemplary machine-readable storage medium may also include one or more of the following features: the lithium metal battery has a normal operating cutoff voltage, wherein the step of allowing includes allowing a voltage generated by the battery to drop below the normal operating cutoff voltage; the depth of discharge (DOD) of the lithium metal battery is 100% at 0% SOC, the method also including providing a maximum DOD associated with both the normal operating range energy and the backup energy of the discharged battery to a load connected to the battery, the DOD 最大备用能量 , where DOD 最大备用能量 >DOD;DOD 最大备用能量 is at least 20% greater than the DOD; instructions for steps for allowing the battery to enter a reserve energy operating range include allowing a reserve energy chemical reaction to occur in the battery to generate electrical energy after the SOC reaches 0%; the positive electrode is formed of a positive electrode material, and wherein the reserve energy chemical reaction includes at least one of a redox reaction between the stripped lithium ions and the electrolyte of the battery and a chemical reaction between the stripped lithium ions and the positive electrode material that causes a phase change of the positive electrode material; the instructions also include calculating a reserve energy capacity value, wherein the calculation is a function of the operating history of the battery.

[0060] In certain further embodiments, a machine-readable storage medium of the present disclosure may include machine-readable instructions for executing a method for operating a load, the machine-readable instructions including instructions for: receiving a battery signal, the battery signal including operating condition information of a lithium metal battery for providing electrical energy to the load; determining whether backup energy capacity of the battery is required based on the battery signal; and sending a backup energy signal to the battery in response to determining that backup energy capacity is required. Such an exemplary machine-readable storage medium may also include one or more of the following features: the battery signal includes information about the remaining amount of normal operating range energy stored in the battery; the instructions for the step of determining include instructions for determining the likelihood that the load will be damaged if power from the battery will immediately cease; the instructions for the step of sending a backup energy signal include instructions for instructing the battery to continue discharging energy after reaching a normal operating range state of charge of 0%; substantially all of the intercalation sites of one or more positive electrodes of the battery are substantially saturated when the battery reaches a normal operating range state of charge of 0%; the instructions for the step of sending a backup energy signal include instructions for instructing the battery to allow the voltage of the battery to drop below the normal operating range cutoff voltage; the instructions for the step of sending a backup energy signal include instructions for instructing the battery to operate in a backup energy operating range; the backup energy operating range is a range in which the battery is charged. An operating range in which substantially all intercalation sites of one or more positive electrodes of the battery are substantially saturated; a reserve energy operating range is an operating range in which the potential is generated by a reserve energy chemical reaction, the reserve energy chemical reaction including at least one of a redox reaction between stripped lithium ions and the electrolyte of the battery and a chemical reaction between the stripped lithium ions and the positive electrode of the battery that causes a phase change of the positive electrode; the battery signal is an indication of a normal operating range energy level of the battery, and the method instructions also include instructions for receiving a reserve energy capacity value indicating a maximum amount of reserve energy; wherein the step of determining whether the reserve energy capacity of the battery is needed includes determining the amount of energy required to transport the load to a safe location; and automatically initializing an autopilot operation to autonomously transport the load to a safe location when the normal operating range energy level plus the reserve energy capacity is less than the determined amount of energy required to transport the load to a safe location plus a threshold.

[0061] The above has been a detailed description of an illustrative embodiment of the present invention. Note that in the specification and the appended claims, connective language, such as used in the phrases "at least one of X, Y, and Z" and "one or more of X, Y, and Z", unless otherwise specifically stated or indicated, should be taken to mean that each item in the connective list may exist in any number excluding every other item in the list or in any number combined with any or all of the other items in the connective list, each of which may also exist in any number. Applying this general rule, the connective phrases in the above examples in which the connective list consists of X, Y, and Z should each cover: one or more of X; one or more of Y; one or more of Z; one or more of X and one or more of Y; one or more of Y and one or more of Z; one or more of X and one or more of Z; and one or more of X, one or more of Y, and one or more of Z.

[0062] Various modifications and additions can be made without departing from the spirit and scope of the present invention. The features of each of the various embodiments described above can be combined with the features of other described embodiments as appropriate to provide a variety of feature combinations in associated new embodiments. In addition, although many separated embodiments are described above, the content described herein is only an illustration of the application of the principles of the present invention. In addition, although the specific method of this article can be illustrated and / or described as being carried out in a specific order, the order is highly variable within common sense to realize the aspects of the present disclosure. Accordingly, this description is intended to be only by way of example, and does not otherwise limit the scope of the present invention.

Claims

1. A method for operating a load, the method comprising: receiving a battery signal, the battery signal including operating condition information of a lithium metal battery for providing electrical energy to the load; determining whether backup energy capacity of the battery is needed based on the battery signal; as well as sending a reserve energy signal to the battery in response to determining that the reserve energy capacity is needed; The backup energy signal includes an instruction for allowing the voltage of the battery to drop below a cut-off voltage of a normal operating range. 2 . The method of claim 1 , wherein the battery signal includes information regarding an amount of normal operating range energy remaining stored in the battery.

3. The method of claim 1, wherein the step of determining includes determining a likelihood that the load would be damaged if power from the battery were to cease immediately.

4. The method of claim 1, wherein the step of sending a reserve energy signal includes instructing the battery to continue discharging energy after reaching a normal operating range state of charge of 0%.

5. The method of claim 4, wherein substantially all of the intercalation sites of one or more positive electrodes of the battery are substantially saturated when the battery reaches the 0% normal operating range state of charge.

6. The method of claim 1 , wherein the step of sending a backup energy signal includes instructing the battery to allow the voltage of the battery to drop to a backup energy voltage and to reach equilibrium at the backup energy voltage until substantially all of the backup energy capacity is discharged, the backup energy voltage being less than the normal operating range cutoff voltage.

7. The method of claim 1, wherein the step of sending a backup energy signal includes instructing the battery to operate in a backup energy operating range.

8. The method of claim 7, wherein the backup energy operating range is an operating range in which substantially all of the intercalation sites of one or more positive electrodes of the cell are substantially saturated.

9. The method of claim 8, wherein the backup energy operating range is an operating range in which the potential is generated by a backup energy chemical reaction, the backup energy chemical reaction including at least one of a redox reaction between the stripped lithium ions and the electrolyte of the battery and a chemical reaction between the stripped lithium ions and the positive electrode of the battery that causes a phase change of the positive electrode.

10. The method of claim 1, wherein the battery signal is an indication of a normal operating range energy level of the battery, the method further comprising: receiving a reserve energy capacity value indicating a maximum amount of reserve energy; wherein the step of determining whether the backup energy capacity of the battery is required comprises determining an amount of energy required to transport the load to a safe location; as well as When the normal operating range energy level plus the reserve energy capacity is less than the determined amount of energy required to transport the load to the safe location plus a threshold, automatically initiating autopilot operation to autonomously transport the load to the safe location.

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