Aerosol Generating Device with Multiple Power Supplies

Abstract

The present invention relates to an aerosol generating device comprising a first power source and a second power source, and an electric circuit comprising a controller configured to supply electric energy from the first power source and the second power source to at least one electric heater. The first power source and the second power source are of different types. The present invention also relates to an aerosol generating system comprising the aerosol generating device. The present invention also relates to a method of generating an aerosol in an aerosol generating device.

Description

[Technical Field]

[0001] The present invention relates to an aerosol generating device comprising a first power supply and a second power supply. The invention has particular application as an aerosol generating device forming part of an aerosol generation system. The invention also relates to a method of generating an aerosol in such an aerosol generating device.

[0002] One type of aerosol generating system is an electrically operated aerosol generating system. Known handheld electrically operated aerosol generating systems typically include an aerosol generating device that includes a battery, control electronics, and an electric heater for heating an aerosol-forming substrate. The aerosol-forming substrate may be housed within a portion of the aerosol generating device. For example, the aerosol generating device may include a liquid storage portion in which a liquid aerosol-forming substrate, such as a nicotine solution, is stored. Alternatively, the aerosol-forming substrate may form part of a separate aerosol-generating article specifically designed for use with the aerosol generating device. The separate aerosol-generating article may include an electric heater. In some embodiments, the aerosol-generating article includes an aerosol-forming substrate, such as a tobacco rod or tobacco plug, and the heater housed within the aerosol-generating device is inserted into or around the aerosol-forming substrate when the aerosol-generating article is inserted into the aerosol-generating device. In other embodiments, the aerosol-generating article includes a heating arrangement in which the article includes a susceptor that is heated by one or more induction coils within the aerosol generating device.

[0003] Typically, during a user experience, power is supplied according to a predetermined heating profile. Such a heating profile may include at least two heating phases, including, but not limited to, a preheating phase and an operating phase. The preheating phase may be shorter than the operating phase. However, during the preheating phase, power consumption may be higher compared to power consumption during the operating phase.

[0004] Because it is generally desirable to have an aerosol generator that can provide multiple experiences, there is a general trend toward using batteries with high energy densities. However, high-energy-density batteries can have fairly high internal resistance, which results in internal power losses and reduces the number of potential user experiences.

[0005] It would be desirable to provide an aerosol generating device with a power supply system that allows for efficient use of stored power.

[0006] It would be desirable to provide an aerosol generating device with a power supply system that allows it to efficiently handle varying power demands during different stages of the user experience.

[0007] It would be desirable to provide an aerosol generating device with a power supply system that allows for an extended period of use for a continuous user experience, or even for multiple user experiences.

[0008] The aerosol generating device according to the present invention comprises a first and a second power supply. The aerosol generating device further comprises an electrical circuit comprising a controller configured to supply electrical energy from the first power supply and the second power supply to the electric heater. The first power supply and the second power supply are of different types.

[0009] The controller is configured to supply electrical energy directly from the first power source and directly from the second power source to the at least one electric heater. Supplying power directly from the first and second power sources means that power is provided to the heater directly from these power sources without intermediate storage in an additional storage unit or one of the power sources of the device. In particular, power from the first power source is not only provided to the second power source, but also provided from the second power source to the heater. Such configurations are known from the prior art, for example, where a rechargeable battery is used exclusively to charge a capacitor and only power from the capacitor is provided to the heater. Instead, in the present invention, the controller is configured to provide power directly to the heater from both power sources.

[0010] The controller is configured to supply electrical energy to the at least one electric heater from the first power source but not via the second power source during at least one period when the at least one electric heater is heated. The controller is configured to supply electrical energy to the at least one electric heater from the second power source but not via the first power source during at least one period when the at least one electric heater is heated.

[0011] The expression "different types of power sources" means that the two power sources are not only different components or entities, but also that the power sources are power sources with different nominal electrical characteristics or properties. These different nominal electrical characteristics or properties lead to different charging and discharging behavior of the power sources. By using power sources with different nominal electrical characteristics, the power flow from the power sources can be advantageously matched to the immediate power demands of the aerosolization process.

[0012] For example, the power supplies may differ with respect to one or more of their construction, chemical composition, nominal energy density, their nominal internal resistance, their nominal output voltage, their nominal output current, and their nominal output power.

[0013] The first power source may have a nominal energy density that is higher than a nominal energy density of the second power source, and the controller may be configured to provide power from the first power source when there is a need to provide power to the electric heater for an extended period of time.

[0014] The first power source may be a battery. The first power source may be a battery having a high energy density. The first power source may be a lithium-ion battery. The first power source may be a lithium manganese cobalt oxide (Li-NMC) battery. The first power source may be a lithium cobalt oxide (LCO) battery. The first power source may be a lithium nickel cobalt aluminum oxide (NCA) battery. The first power source may be a lithium polymer battery (LiPo). Such a power source may have an energy density of about 150 to 220 watt-hours per kilogram.

[0015] The first power supply may be further configured to provide power to the controller and any other electronic components of the aerosol generating device.

[0016] Power sources with high energy densities may have relatively higher internal resistance than other types of power sources, which can have drawbacks when drawing high currents from them.

[0017] When a battery is connected to a load, a current I is drawn. This current I is proportional to the battery's output voltage V. bat , and the total load, i.e., the internal battery resistance R int , and the load resistance R load It depends on the sum of the battery resistance R int depends on the battery chemistry used. Load resistance R load depends mainly on the type of load to which the current is applied. In an aerosol generator, the load resistance R load can essentially correspond to the heater resistance. The power P dissipated in the resistive element R is defined as: (1) P=RI 2

[0018] Therefore, the power dissipated in the battery is proportional to the internal resistance R int and, importantly, the square of the current drawn therefrom. High currents can therefore lead to increased power dissipation, especially in batteries. High power drain can be particularly detrimental to high energy density batteries and should therefore be sought to be avoided.

[0019] At the beginning of the preheating stage, the power dissipation in the battery may be particularly high because, at this stage, the resistive heater is still at ambient temperature and therefore has a relatively low resistance. At room temperature, the typical resistance (R load ) may be approximately 1 ohm. This value typically increases with increasing heater temperature. The internal resistance R of a conventional Li-NMC battery int may be approximately 0.1 ohms. The fully loaded open circuit voltage (i.e., no load) of a Li-NMC battery, Vbat, is 3.7 volts. Therefore, if a current of 3.8 amps is drawn, R int and R load The power dissipated in R is 1.44 W and 14.44 W, respectively. int The power lost in this example represents 9% of the total power consumption. In other words, about 1 / 10 of the available energy is lost in the battery's internal resistance. This reduces the energy available to power the electric heater. This in turn reduces the potential number of smoking experiences by the same factor. Furthermore, the battery's internal resistance R int is known to increase with temperature, and since batteries tend to get warmer during high power drain, this leads to more energy dissipation during use.

[0020] To reduce such internal energy losses, the aerosol generating device includes a second power source having different nominal electronic characteristics. The second power source may be a battery having a lower internal resistance than the first power source. The second power source may be a LiFePO4 battery. The second power source may also be an electric double layer capacitor.

[0021] The typical internal resistance of a LiFePO4 battery is less than 0.1 ohms. The internal resistance of an electric double layer capacitor is also less than 0.1 ohms, typically less than 0.03 ohms. The effective internal resistance of such power sources can be further reduced by connecting the power sources in parallel. Therefore, the typical internal resistance of such power sources is significantly lower than that of typical other power sources, especially Li-NMC batteries. Because of their low internal resistance, such power sources are suitable for delivering high currents and therefore higher powers, comparable to other power sources.

[0022] A power source with low internal resistance may have an energy density of up to 90-120 watt-hours per kilogram. This energy density may be less than that of a typical Li-NMC battery. However, because its internal resistance is lower than that of the first power source, the second power source may be better suited to providing high power drain for short periods of time. During this short period, a high current can be delivered to the electrical load while the amount of dissipated energy is reduced.

[0023] The controller of the aerosol generating device may be configured to control the power supply from both power sources to the electric heater. The controller may be configured to supply power to the electric heater according to the instantaneous power demands of the aerosolization process. The controller of the aerosol generating device may further comprise a microcontroller unit. The microcontroller unit may be configured to regulate the power supply to the electric heater from one or both of the power sources.

[0024] The controller may be configured to supply electrical energy from the first power source and the second power source to the at least one electric heater simultaneously or at different times. The controller may be configured to supply electrical energy from the first power source and the second power source to the at least one electric heater simultaneously or at different times during a user experience or during a heating profile for generating an aerosol.

[0025] The controller may be configured to provide power to the electric heater of the aerosol generating device according to a predetermined heating profile. The predetermined heating profile may include at least a first heating stage and a second heating stage. A different amount of heating power may be provided to the electric heater in the first heating stage of the heating profile compared to the second heating stage. A higher current, and therefore a higher amount of power, may be provided to the electric heater in the first heating stage.

[0026] The first and second heating stages may also differ in terms of their duration. For example, the first heating stage may be shorter than the second heating stage. The first heating stage may last for a maximum of 20 seconds. The first heating stage may last for a maximum of 30 seconds. The first heating stage may last for a maximum of 40 seconds. The second heating stage may last for at least 60 seconds. The second heating stage may last for at least 120 seconds. The second heating stage may last for a maximum of 300 seconds. The second heating stage may last for a maximum of 500 seconds.

[0027] The first heating stage may also be defined in terms of a temperature threshold being reached. For example, the first heating stage may continue until the measured temperature reaches a predetermined threshold temperature. The first heating stage may continue until the heater temperature reaches a predetermined threshold temperature.

[0028] The controller of the aerosol generating device may be configured such that, in the first heating stage, power is supplied to the electric heater from the second power source. The controller of the aerosol generating device may be configured such that, in the first heating stage, power is supplied to the electric heater from both power sources, from the first power source and from the second power source. By providing the power required in the first heating stage from the second power source, internal power losses caused by the relatively large internal resistance of the first power source are reduced. This effect is, of course, most significant when all the required power is provided by the second power source. However, this advantageous effect is also achieved when the required power is provided from both power sources, from the first power source and the second power source.

[0029] The first heating stage may be a preheating stage for preheating the electric heater to an operating temperature. The operating temperature is a temperature sufficient to generate an aerosol. In the preheating stage, the electric heater assembly including the aerosol-forming substrate needs to be heated from ambient temperature to the operating temperature. Therefore, the preheating stage requires the supply of a large amount of power in a relatively short period of time. Therefore, the preheating stage generates a high current drain in a fairly short period of time.

[0030] The controller of the aerosol generating device may be further configured to supply power to the electric heater only from the first power source during the second heating stage. The second heating stage may be an operating stage in which the aerosol generating device can be used to generate inhalable aerosols. Because the operating stage does not require a significant temperature increase but still requires providing the heater assembly with a sufficient amount of power to maintain the heater assembly at an operating temperature, the current drain during the operating stage is typically less than the current drain during the preheating stage. However, the operating stage typically lasts for a significantly longer period than the preheating stage. Therefore, the overall energy supplied during the operating stage is typically higher than the energy supplied during the preheating stage. Therefore, using a power source with a high energy density advantageously allows for an increased usage time of the aerosol generating device during the operating stage.

[0031] The first and second power supplies may advantageously be connected in parallel. Paralleling multiple power supplies having the same nominal voltage but otherwise different electrical characteristics is well within the skill of one skilled in the art.

[0032] If the power sources have different nominal voltages, the first power source and the second power source can be connected in parallel. However, in this case, the electrical circuit of the aerosol generating device may need to be equipped with a voltage control. The voltage control may be a DC / DC converter that matches the different nominal voltages of the first power source and the second power source. The voltage control may then be controlled by the controller of the aerosol generating device.

[0033] The controller of the aerosol generator may be configured to control the power supply from the first and second power sources via two switches, which may advantageously be configured as MOSFET switches controlled by the aerosol generator controller.

[0034] Connecting multiple power supplies in parallel can bring other advantages. Because the total current I corresponds to the sum of the currents I provided by the individual power supplies, the effective current drain on each power supply can be significantly smaller than when using only one power supply. Therefore, less current is drawn from each power supply, and the total energy dissipated in the two power supplies is lower than the energy dissipated internally when only one power supply is connected. Power dissipation scales linearly with resistance R, due to the fact that it scales squarely with current I, as shown in equation (1) above.

[0035] The aerosol generating device may further comprise a power connector for receiving electrical energy from an external power source. The charging process may be controlled according to any technique known to those skilled in the art.

[0036] The controller of the aerosol generating device may be configured to control the recharging process of the first and second power sources from an external power source. The controller of the aerosol generating device may be configured to control the recharging process so that the first and second power sources are recharged simultaneously. The controller of the aerosol generating device may be configured to control the recharging so that the first power source is recharged first. Recharging the first power source first may be advantageous because the first power source is used to power the control electronics of the aerosol generating device. Operation of the aerosol generating device may not be possible with a first power source that is not fully charged.

[0037] The controller may be further configured to control recharging such that the first power source is used to recharge the second power source. Because the overall capacity of the first power source may be greater than the capacity of the second power source, the first power source may be used to recharge the second power source. Using the first power source to recharge the second power source has the added advantage that such recharging can continue even when the aerosol generating device is disconnected from the external power source. This increases the usability of the device and therefore improves the user experience.

[0038] The internal energy loss due to energy dissipation within the first power supply is proportional to the current drain according to equation (1) above. Therefore, it may be advantageous to keep the power drain from the first power supply as low as possible. To this end, the controller may be configured to prevent the second power supply from being recharged from the first power supply as long as power is supplied from the first power supply to the electric heater. In other words, the controller may be configured to prevent the second power supply from being recharged from the first power supply during an operational phase in which the first power supply is used to supply power to the electric heater.

[0039] However, it may also be advantageous to have a controller configured to provide power from the first power source to the second power source and to the electric heater simultaneously upon request from a user. Although more energy may be dissipated internally within the first power source, this configuration may have the added benefit of completing the recharging process of the second power source more quickly. A trade-off must be found between the recharging speed of the second power source and losses in the internal resistance of the first power source.

[0040] The controller of the aerosol generating device may be configured to initiate recharging of the second power source from the first power source when the output voltage of the second power source drops below a threshold voltage. The charging threshold voltage may be configured to be approximately 2.5 volts. The charging threshold voltage may be configured to be approximately 2.0 volts. The charging threshold voltage may be configured to be approximately 0 volts.

[0041] As used herein, the term "user experience" refers to the use of a device to generate an aerosol. During a user experience, an electric heater is activated and / or a predetermined heating profile is applied to generate an aerosol. A user typically takes multiple puffs during a user experience. The duration of a user experience may depend on the user's preferences and may typically last up to about 300 seconds.

[0042] The airflow sensor may be configured to measure airflow through the aerosol generating device to determine when a consumer is inhaling the aerosol generating device or an aerosol generating system including the aerosol generating device. The controller may be configured to modify the rate at which electrical energy is supplied from the first power source to the at least one heater based on the measured airflow through the aerosol generating device. The controller may be configured to increase the rate at which electrical energy is supplied from the first power source to the at least one heater when airflow through the aerosol generating device increases. The controller may be configured to decrease the rate at which electrical energy is supplied from the first power source to the at least one heater when airflow through the aerosol generating device decreases.

[0043] In embodiments in which the at least one additional electrical component comprises at least one user input device, the at least one user input device may comprise at least one of a push button input device, a capacitive input device, and a voice input device.

[0044] In embodiments in which the at least one additional electrical component comprises at least one feedback device, the at least one feedback device may comprise at least one of an LED, an LCD, a speaker, and a tactile feedback device.

[0045] The at least one electric heater may comprise at least one of a resistive heater and an induction heater.

[0046] The aerosol-generating device may include a liquid reservoir and a liquid aerosol-forming substrate stored in the liquid reservoir. During use, an electric heater heats a small portion of the liquid aerosol-forming substrate to vaporize the small portion. The liquid aerosol-forming substrate preferably includes a tobacco-containing material containing volatile tobacco flavor compounds that are released from the liquid upon heating. Alternatively, or additionally, the liquid aerosol-forming substrate may include a non-tobacco material. The liquid aerosol-forming substrate may include water, a solvent, ethanol, a plant extract, and a natural or artificial flavor. Preferably, the liquid aerosol-forming substrate further includes an aerosol former.

[0047] As used herein, the term "aerosol former" is used to describe any suitable known compound or mixture of compounds that facilitates the formation of an aerosol upon use. Suitable aerosol formers are substantially resistant to thermal decomposition at the operating temperatures of the aerosol generating device. Examples of suitable aerosol formers are glycerin and propylene glycol.

[0048] The aerosol-generating device may further comprise a capillary wick in communication with the liquid storage portion. The capillary wick is positioned to contact a liquid aerosol-forming substrate in the liquid storage portion. During use, the liquid aerosol-forming substrate is transferred from the liquid storage portion along the capillary wick by capillary action, where it is heated by the electric heater. In embodiments in which the electric heater comprises an induction heater, the aerosol-generating device may further comprise a susceptor. During use, the induction heater heats the susceptor, and the liquid aerosol-forming substrate is transferred from the liquid storage portion to the susceptor via the capillary wick.

[0049] The aerosol-generating device may include a cavity for receiving an aerosol-generating article including an aerosol-forming substrate. The at least one electric heater may include an elongated heater configured to be inserted into the aerosol-generating article when the aerosol-generating article is received in the cavity. The elongated heater may have any suitable shape that facilitates insertion into the aerosol-generating article. For example, the elongated heater may be a heater blade. Preferably, the elongated heater is a resistance heater.

[0050] The at least one heater may comprise a heater positioned adjacent to the outer surface of the aerosol-generating article when the aerosol-generating article is received in the cavity. The at least one heater may comprise a substantially annular heater configured to surround at least a portion of the aerosol-generating article when the aerosol-generating article is received in the cavity. The at least one heater may comprise a substantially planar heater positioned adjacent to an edge of the aerosol-generating article when the aerosol-generating article is received in the cavity. Preferably, the heater positioned adjacent to the outer surface of the aerosol-generating article when the aerosol-generating article is received in the cavity is an induction heater.

[0051] As used herein, the terms "interior" and "exterior" are used to refer to the relative positions of components of an aerosol generating device or parts of a component of an aerosol generating device, e.g., an inner surface of a component faces toward the interior of the device, and an outer surface of a component faces toward the exterior of the device.

[0052] The present invention also relates to an aerosol generation system comprising the aerosol generation device described above and at least one electric heater configured to be removably attached to the aerosol generation device. The aerosol generation system may further comprise a cartridge comprising the at least one electric heater and an aerosol-forming substrate.

[0053] The aerosol-generating system may also include the aerosol-generating article and aerosol-generating device described above. The aerosol-generating article may include an aerosol-forming substrate. The aerosol-generating device preferably includes a recess for receiving the aerosol-generating article.

[0054] The aerosol-generating article may include a liquid reservoir and a liquid aerosol-forming substrate stored in the liquid reservoir. During use, an electric heater heats a small portion of the liquid aerosol-forming substrate to vaporize the small portion. The liquid aerosol-forming substrate preferably includes a tobacco-containing material containing volatile tobacco flavor compounds that are released from the liquid upon heating. Alternatively, or additionally, the liquid aerosol-forming substrate may include a non-tobacco material. The liquid aerosol-forming substrate may include water, a solvent, ethanol, a plant extract, and a natural or artificial flavor. Preferably, the liquid aerosol-forming substrate further includes an aerosol former.

[0055] The aerosol-generating article may further comprise a capillary wick in communication with the liquid storage portion. The capillary wick is positioned to contact a liquid aerosol-forming substrate within the liquid storage portion. During use, the liquid aerosol-forming substrate is transferred from the liquid storage portion along the capillary wick by capillary action, where it is heated by the electric heater. In embodiments in which the electric heater comprises an induction heater, the aerosol-generating article may further comprise a susceptor. During use, the induction heater heats the susceptor, and the liquid aerosol-forming substrate is transferred from the liquid storage portion to the susceptor via the capillary wick.

[0056] The aerosol-generating article may comprise a solid aerosol-forming substrate. The aerosol-forming substrate may comprise tobacco. The aerosol-forming substrate may comprise a tobacco-containing material containing volatile tobacco flavor compounds that are released from the substrate upon heating. The aerosol-forming substrate may comprise a non-tobacco material. The aerosol-forming substrate may comprise a tobacco-containing material and a non-tobacco-containing material. In embodiments in which the electric heater comprises an induction heater, the aerosol-generating article may further comprise a susceptor. The susceptor is preferably located within the aerosol-forming substrate.

[0057] The aerosol-forming substrate may comprise at least one aerosol former. Suitable aerosol formers include, but are not limited to, polyhydric alcohols (such as propylene glycol, triethylene glycol, 1,3-butanediol, and glycerin), esters of polyhydric alcohols (such as glycerol monoacetate, diacetate, or triacetate), and aliphatic esters of mono-, di-, or polycarboxylic acids (such as dimethyl dodecanedioate and dimethyl tetradecanedioate).

[0058] Preferred aerosol formers are polyhydric alcohols such as propylene glycol, triethylene glycol, 1,3-butanediol, and most preferably glycerin, or mixtures thereof.

[0059] The aerosol-forming substrate may comprise a single aerosol former, or alternatively, the aerosol-forming substrate may comprise a combination of two or more aerosol formers.

[0060] The aerosol-forming substrate may contain more than 5% aerosol former on a dry weight basis.

[0061] The aerosol-forming substrate may have an aerosol-forming content of from about 5 percent to about 30 percent on a dry weight basis.

[0062] The aerosol-forming substrate may have an aerosol-former content of approximately 20 percent on a dry weight basis.

[0063] The aerosol-generating article may comprise an aerosol-forming substrate comprising a first aerosol-forming substrate comprising a nicotine source and a second aerosol-forming substrate comprising an acid source. In use, the electric heater heats the first and second aerosol-forming substrates to volatilize the nicotine and acid, such that the nicotine and acid react together in the gas phase to form an aerosol of nicotine salt particles. In embodiments in which the electric heater comprises an induction heater, the aerosol-generating article may further comprise a susceptor. The susceptor is preferably positioned to heat both the nicotine source and the acid source.

[0064] The nicotine source may include one or more of nicotine, nicotine base, a nicotine salt (such as nicotine-HCl, nicotine tartrate, or nicotine bitartrate), or a nicotine derivative.

[0065] The nicotine source may include natural or synthetic nicotine.

[0066] The nicotine source may include pure nicotine, a solution of nicotine in an aqueous or non-aqueous solvent, or a liquid tobacco extract.

[0067] The nicotine source may further comprise an electrolyte-forming compound, which may be selected from the group consisting of alkali metal hydroxides, alkali metal oxides, alkali metal salts, alkaline earth metal oxides, alkaline earth metal hydroxides, and combinations thereof.

[0068] For example, the nicotine source may include an electrolyte-forming compound selected from the group consisting of potassium hydroxide, sodium hydroxide, lithium oxide, barium oxide, potassium chloride, sodium chloride, sodium carbonate, sodium citrate, ammonium sulfate, and combinations thereof.

[0069] In certain embodiments, the nicotine source may comprise an aqueous solution of nicotine, nicotine base, nicotine salt, or nicotine derivative and an electrolyte-forming compound.

[0070] The nicotine source may further include other components, including, but not limited to, natural flavors, artificial flavors, antioxidants, and the like.

[0071] The acid source may comprise an organic acid or an inorganic acid. Preferably, the acid source comprises an organic acid, more preferably a carboxylic acid, and most preferably lactic acid or an α-keto acid or a 2-oxo acid.

[0072] Preferably, the acid source comprises an acid selected from the group consisting of lactic acid, 3-methyl-2-oxopentanoic acid, pyruvic acid, 2-oxopentanoic acid, 4-methyl-2-oxopentanoic acid, 3-methyl-2-oxobutanoic acid, 2-oxooctanoic acid, and combinations thereof. Preferably, the acid source comprises lactic acid or pyruvic acid.

[0073] The present invention also relates to a method for generating an aerosol in an aerosol generating device as described herein, the method comprising supplying electrical energy to at least one electric heater from a first power source and a second power source, the electrical energy from the first power source and the second power source being provided to the heater either simultaneously or at different times, the first power source and the second power source being different types of power sources.

[0074] The controller may provide power to the heater according to a predetermined heating profile. The predetermined heating profile may include at least a first heating stage and a second heating stage. In the first heating stage, the controller may supply a different amount of heating power to the electric heater than in the second heating stage.

[0075] The first heating stage may be a preheating stage for preheating the electric heater from ambient temperature to an operating temperature, wherein power is supplied to the electric heater from a second power source, which has a lower internal resistance and a lower energy density than the first power source.

[0076] The second heating stage may be an operating stage in which the aerosol generating device is used to generate an inhalable aerosol. In the operating stage, power may be supplied to an electric heater from a first power source, which has a higher internal resistance and a higher energy density than the second power source.

[0077] By powering the heaters from different power sources according to a predetermined heating profile, internal energy losses can be reduced. Because only a limited amount of energy is available in portable devices, efficient use of stored energy, especially reducing energy losses, allows for longer usage times of the portable device.

[0078] The aerosol generating device may further include a power connector for receiving electrical energy from an external power source. In this regard, the controller may control a recharging process of the first and second power sources from the external power source. The controller may control the recharging process such that the first power source is used to recharge the second power source. [Example]

[0079] The following provides a non-exhaustive list of non-limiting examples, any one or more of the features of which may be combined with any one or more features of another example, embodiment, or aspect described herein.

[0080] Example 1: An aerosol generating device comprising a first power source and a second power source, and an electrical circuit comprising a controller configured to supply electrical energy from the first power source and the second power source to at least one electric heater, wherein the first power source and the second power source are different types of power sources. Example 2: 2. The aerosol generating device of example 1, wherein the controller is configured to supply electrical energy from the first power source and the second power source directly to the at least one electric heater. Example 3: 3. The aerosol generating device according to any one of Examples 1 and 2, wherein the first power source has a higher energy density than the second power source. Example 4: 4. The aerosol generating device according to any one of Examples 1 to 3, wherein the first power source is a battery, preferably a high energy density battery, preferably a Li-Ion battery, preferably a Li-NMC, Li-LCO, Li-NCA, or LiPo battery. Example 5: 5. An aerosol generation device according to any one of Examples 1 to 4, wherein the first power source is configured to power the controller and any other electronic components of the aerosol generation device. Example 6: 6. The aerosol generating apparatus according to any one of Examples 1 to 5, wherein the second power source is a battery having an internal resistance lower than the internal resistance of the first power source. Example 7: 7. The aerosol generating device according to any one of Examples 1 to 6, wherein the second power source is a LiFePO4 battery or an electric double layer capacitor. Example 8: 8. The aerosol generating apparatus according to any one of Examples 1 to 7, wherein the first power supply and the second power supply are connected in parallel. Example 9: 9. The aerosol generating device according to any one of Examples 1 to 8, wherein the first power supply and the second power supply have different nominal voltages. Example 10: 10. The aerosol generating device according to any one of Examples 1 to 9, wherein the electrical circuit comprises a DC / DC converter that matches the different nominal voltages of the first power supply and the second power supply. Example 11: 11. The aerosol generating device according to any one of Examples 1 to 10, wherein the controller comprises a microcontroller unit. Example 12: 12. An aerosol generating device according to any one of Examples 1 to 11, wherein the controller is configured to provide power to the heater according to a predetermined heating profile. Example 13: An aerosol generating device as described in Examples 1 to 12, wherein the predetermined heating profile includes at least a first heating stage and a second heating stage, and different amounts of heating power are provided to the electric heater in the first heating stage and the second heating stage. Example 14: 14. The aerosol generating device of any one of Examples 1 to 13, wherein during the first heating stage, the controller is arranged to supply power to the electric heater from the second power source. Example 15: 15. The aerosol generating apparatus of any one of Examples 1 to 14, wherein during the first stage, the controller is configured to supply power to the electric heater from the first power source and the second power source. Example 16: 16. The aerosol generating device of any one of Examples 1 to 15, wherein during the second heating stage, the controller is arranged to supply power to the electric heater only from the first power source. Example 17: 17. An aerosol generating apparatus according to any one of Examples 1 to 16, wherein the first heating stage is a preheating stage for preheating an electric heater to an operating temperature. Example 18: 18. An aerosol generating device according to any one of Examples 1 to 17, wherein the second heating stage is an operating stage in which the aerosol generating device is used to generate an inhalable aerosol. Example 19: 19. An aerosol generating apparatus according to any one of Examples 1 to 18, wherein the controller is arranged to control the power supply from the first and second power sources via two switches, preferably two MOSFET switches. Example 20: 20. An aerosol generating device according to any one of Examples 1 to 19, wherein the aerosol generating device further comprises a power connector for receiving electrical energy from an external power source, and wherein the controller is arranged to control recharging of the first and second power sources from the external power source. Example 21: 21. An aerosol generating device according to any one of Examples 1 to 20, wherein the controller is arranged to control the recharging of the first and second power sources such that they are recharged simultaneously. Example 22: 22. An aerosol generating device according to any one of Examples 1 to 21, wherein the controller is arranged to control recharging such that the first power source is recharged first. Example 23: 23. An aerosol generating device according to any one of Examples 1 to 22, wherein the controller is configured to control recharging such that the first power source is used to recharge the second power source. Example 24: 24. The aerosol generating device of any one of Examples 1 to 23, wherein the controller is configured to prevent the second power source from being recharged from the first power source as long as power is supplied to the electric heater. Example 25: 25. The aerosol generating device of any one of Examples 1 to 24, wherein the controller is configured to simultaneously power the second power supply and the electric heater from the first power supply. Example 26: 26. The aerosol generating device of any one of Examples 1 to 25, wherein the controller is configured to initiate recharging of the second power source from the first power source when the output voltage of the second power source falls below a threshold voltage. Example 27: An aerosol generating device according to any one of Examples 1 to 26, wherein the threshold voltage is 2.5 volts, preferably the threshold voltage is 2.0 volts, preferably the threshold voltage is 0 volts. Example 28: 28. The aerosol generating device according to any one of Examples 1 to 27, further comprising at least one electric heater. Example 29: An aerosol generating device described in any one of Examples 1 to 28, wherein the controller is configured to supply electrical energy from the first power source and the second power source to the at least one electric heater simultaneously or at different times. Example 30: An aerosol generating device described in any one of Examples 1 to 29, wherein the controller is configured to supply electrical energy from a first power source and a second power source to at least one electric heater simultaneously or at different times during a user experience or during a heating profile for generating an aerosol. Example 31: An aerosol generation system comprising the aerosol generation device according to any one of Examples 1 to 30 and at least one electric heater configured to be removably attached to the aerosol generation device. Example 32: 32. The aerosol-generating system of Example 31, further comprising a cartridge comprising at least one electric heater and an aerosol-forming substrate. Example 33: A method for generating an aerosol in an aerosol generating device, comprising supplying electrical energy to at least one electric heater from a first power source and a second power source, wherein the electrical energy from the first power source and the second power source is provided to the heater either simultaneously or at different times, and the first power source and the second power source are different types of power sources. Example 34: 34. The method of example 33, wherein the controller provides power to the heater according to a predetermined heating profile. Example 35: 35. The method of claim 34, wherein the predetermined heating profile includes at least a first heating stage and a second heating stage, and different amounts of heating power are provided to the electric heater in the first heating stage and the second heating stage. Example 36: 36. The method of claim 35, wherein the first heating step is a preheating step for preheating an electric heater to an operating temperature, and in the preheating step, power is supplied from a second power source having a lower internal resistance and a lower energy density than the first power source. Example 37: The method of any one of Examples 35 and 36, wherein the second heating stage is an operating stage in which the aerosol generating device is used to generate an inhalable aerosol, and wherein, in the operating stage, power is supplied from a first power source having a higher internal resistance and a higher energy density than the second power source. Example 38: The method of any one of Examples 33 or 37, wherein the aerosol generating device further comprises a power connector for receiving electrical energy from an external power source, and the controller controls recharging of the first and second power sources from the external power source. Example 39: 39. The method of any one of claims 1 to 38, wherein the controller controls the recharging such that the first power source is used to recharge the second power source. Example 40: The method of any one of Examples 33-39, wherein electrical energy from the first power source and the second power source is provided to the heater either simultaneously or at different times during a user experience or heating profile for generating the aerosol.

[0081] Features described with respect to one aspect or embodiment may equally apply to other aspects or embodiments of the invention, in particular method aspects may apply to apparatus aspects and vice versa. [Brief explanation of the drawings]

[0082] The invention will now be further described, by way of example only, with reference to the accompanying drawings in which:

[0083] [Figure 1] FIG. 1 shows an aerosol generating system comprising an aerosol generating device and an aerosol-generating article. [Figure 2] Figure 2 shows the electronic scheme of a battery connected to a load. [Figure 3] FIG. 3 shows an implementation of power control in the aerosol generating device according to FIG. [Figure 4] FIG. 4 shows various electrical signals from the battery during operation of the aerosol generating device according to FIG. DETAILED DESCRIPTION OF THE INVENTION

[0084] 1 shows an aerosol generation system 10 comprising an aerosol generating device 12 and an aerosol-generating article 40. The aerosol generating device 12 comprises a housing 14 defining an interior compartment 16.

[0085] The aerosol generating device 12 includes a first power source 18 and a second power source 20, an airflow sensor 24, a feedback device 26, a controller 28, an input device 30, and an electric heater 32, all located within the interior compartment 16. The electric heater 32 is an annular resistive external heater. The first power source 18 is a Li-NMC (lithium nickel manganese cobalt oxide) battery having a nominal output voltage of 3.6 volts, an internal resistance of approximately 0.1 ohms, and an energy density of approximately 200 watt-hours per kilogram (Wh / kg). The first power source is configured to provide electrical energy to all electrical components of the aerosol generating device, including the airflow sensor 24, the feedback device 26, the controller 28, the input device 30, and the electric heater 32.

[0086] The second power source 20 is an LFP (lithium iron phosphate) battery having a nominal output voltage of 3.2 volts, an internal resistance of approximately 0.01 ohms, and an energy density of approximately 100 watt-hours per kilogram (Wh / kg). The second power source 20 is configured to supply electrical energy to the electric heater 32.

[0087] Controller 28 is configured to control the supply of electrical energy from first power source 18 and second power source 20 to other electrical components within interior compartment 16 .

[0088] The aerosol-generating system 10 further comprises an aerosol-generating article 40 that is received in the cavity 34 of the aerosol-generating device 12 during use. The aerosol-generating article 40 comprises an aerosol-forming substrate 42, a hollow acetate tube 44, a polymeric filter 46, a mouthpiece 48, and an outer wrapper 50. The aerosol-forming substrate 42 comprises a plug of tobacco, and the mouthpiece 48 comprises a plug of cellulose acetate fiber.

[0089] During use, the controller 28 supplies electrical energy from the power sources 18, 20 to the electric heater 32 to resistively heat the aerosol-forming substrate 42. The energy supply to the electric heater is controlled by the controller according to a predetermined heating profile. This heating profile includes at least a preheating phase and an operating phase. During the preheating phase, the heater is heated from ambient conditions to approximately 220 degrees Celsius. The preheating phase is fairly short, lasting only about 25 seconds. During the operating phase, the heater is further heated to its operating temperature of approximately 240 degrees Celsius. The operating phase continues until the user decides to stop the experience, typically lasting about 180-300 seconds.

[0090] During the operating phase, the tobacco in the aerosol-forming substrate 42 is heated to an operating temperature and volatile compounds are released from the tobacco for delivery to the user. The feedback device 26 is configured to provide feedback to the user regarding the status of the operating mode of the aerosol generation system.

[0091] Figure 2 shows a schematic diagram of a battery 22 connected to a load 23. The battery 22 has an output voltage V bat and internal resistance R int The load 23 is shown schematically as comprising a voltage source providing a resistor Rload The voltage V applied to the load 23 is load is the battery output voltage V bat When the battery 22 is connected to a load 23, a current I is drawn. This current is proportional to the voltage V of the battery. bat , and the total load, i.e., the internal battery resistance R int and the load resistance R load The former depends on the battery chemistry used, and the latter mainly depends on the heater resistance. The power dissipated in the resistive element, P, is generally given by P=R*I 2 (see equation (1) above). Therefore, if high heating power is required, a high heating current must be drawn from the battery. However, the higher the current drawn from the battery, the more power is dissipated in the battery's internal resistance.

[0092] A conventional resistance heater used in the embodiment of Figure 1 has a resistance of about 1 ohm. The internal resistance of a Li-NMC battery is about 0.1 ohms. Therefore, the power dissipated in the internal resistance of battery 22 in the schematic diagram of Figure 2 is about one-tenth of the power stored in battery 22. While increasing the amount of energy that can be stored in a Li-NMC battery, the high internal resistance does not favor drawing large currents from such a battery.

[0093] Compared to Li-NMC batteries, LFP batteries may have lower energy density, but also lower internal resistance. Therefore, dissipative energy losses are significantly reduced, especially when high currents are delivered. High currents are delivered especially during the preheating stage of an aerosol generating device. However, because the preheating stage lasts only for a limited period of time, the overall energy required during the preheating stage is also limited. The electrical energy stored in an LFP battery suitable for use in a portable device is sufficient to provide the electrical heating power required during the preheating stage.

[0094] Figure 3 shows a schematic diagram illustrating the power supply system within the aerosol generation system of Figure 1. A first power supply 18 has a nominal voltage V of about 3.7 volts. S1and an internal resistance R of approximately 0.1 ohms int1 The first power source 18 is a Li-NMC battery having a voltage of 0.1 V. This first power source 18 is used to power the controller 28. Furthermore, the first power source 18 provides power to the electric heater during the operating phase. Power is delivered via a switch 36.

[0095] The second power source 20 is an LFP battery with a nominal voltage V of approximately 3.2 volts. S2 2, delivering a lower internal resistance R of less than 0.01 ohms int2 The second power supply is connected to the heater resistor R load is low, i.e., when it is cold. The second power supply 20 is capable of delivering high power and high current I2 for a fairly short period of time, such as during the preheating stage or part of the preheating stage. The second power supply 20 provides power to the electric heater via a switch 38.

[0096] The controller switches from the first power source 18 to the second power source 20 using two switches 36, 38. The switches are MOSFET transistors. The nominal battery voltage V S1 , V S2 , and the internal resistance R int1 , R int2 Since the power supplies 18, 20 are not identical, the electronic circuitry within the aerosol generator includes a voltage control 29 controlled by a controller 28. The voltage control 29 includes a DC / DC converter that matches the voltage from the two power supplies 18, 20.

[0097] Connecting batteries in parallel reduces the total current required Ioad I 1と Since it is divided between I2 and R int1 and R int2 Therefore, the current drawn from each battery is less, and the total energy dissipated in the two batteries is less than the energy dissipated internally when only one battery is connected. Power dissipation is linear with resistance R, but this is due to the fact that it is squared with current I, as shown in equation (1).

[0098] Figure 4 shows electrical signals measured at the battery level in a typical aerosol generating device as shown in Figure 1. The electrical signals shown in Figure 4 correspond to instantaneous power voltage 50, instantaneous power current 52, instantaneous power 54, average power 56, and heater resistance 58 measured by the device firmware over a 50 millisecond period.

[0099] FIG. 4 shows these electrical signals throughout the entire user experience, which spans approximately 260 seconds. The first 25 seconds represent the preheat phase. During the preheat phase, the heater temperature increases from ambient temperature to a preheat temperature of approximately 220 degrees Celsius. As seen in FIG. 58, heater resistance 58 thereby increases from 1.0 ohms to approximately 1.15 ohms, representing a 15 percent increase. Throughout the entire user experience, heater resistance 58 remains at this increased resistance level.

[0100] The electric heater is powered using pulse-width modulation (PWM) mode. The power supply is controlled by the aerosol generator firmware and averaged over a 50-millisecond period. This average power is shown in graph 56 of FIG. 4. This average power value starts at 10.8 watts, at a maximum value defined in the firmware. Approximately 10 seconds into the preheat phase, the average power level begins to decrease but remains at an increased level throughout the preheat phase. The initial instantaneous power 54 is measured to be as high as 13.5 watts, decreasing to 11.6 watts after 12 seconds of preheating. Meanwhile, with a duty cycle approaching 100%, the battery is under heavy demand, meaning a high current is drawn from it. This is also evident from the instantaneous current 52 shown in FIG. 4. At the beginning of the preheat phase, when the electric heater is still cold and has an electrical resistance of approximately 1 ohm, an instantaneous current of approximately 3.7 amps is drawn. The heater resistance reached its high value of about 1.15 ohms after the first 12 seconds of the preheat phase.

[0101] During the transition phase, which lasts from 25 to 60 seconds, the average power 56 decreases further, indicating a continuously decreasing duty cycle. After 60 seconds of operation, and until the end of the user experience, the average power 56 is in the range of 2-3 watts. However, due to the on / off mode of heater operation, the instantaneous power 54 still reaches a higher value of approximately 11-12 watts during this portion of the operation phase. Because the duty cycle during the operation phase is much lower, at only 20-30 percent, the battery has more time to recover between pulses and is therefore less demanding.

[0102] The instantaneous power voltage 50 remained rather constant throughout the user experience. The instantaneous power voltage 50 was at a level of 3.7 volts at the beginning of the user experience and decreased slightly to 3.6 volts towards the end of the user experience.

[0103] The high load and high current drain during the preheating stage can result in high resistive losses, which can additionally affect the lifespan of Li-NMC batteries. Supplying power during this stage from a different type of battery, namely an LFP battery, improves the user experience, as these batteries are better suited to supplying large amounts of power. The use of high-energy-density Li-NMC batteries, primarily during the operating stage, allows for more efficient use of large amounts of stored energy, potentially enabling multiple consecutive user experiences without the need for intermediate recharging.

Claims

1. Aerosol generator, The first power supply and the second power supply, The electrical circuit includes a controller configured to supply electrical energy to at least one electric heater from the first power source and the second power source, The first power supply and the second power supply are different types of power supplies. The first power source is a Li-NMC, Li-LCO, Li-NCA, or LiPo battery, and the second power source is a LiFePO4 battery. The controller is configured to supply power to the heater according to a predetermined heating profile, The predetermined heating profile includes at least a first heating stage and a second heating stage, wherein different amounts of heating power are supplied to the electric heater in the first heating stage and the second heating stage. The first heating step is a preheating step for preheating the electric heater to its operating temperature. An aerosol generator in which the second heating step is an operating step used by the aerosol generator to generate an aerosol that can be inhaled.

2. The aerosol generator according to claim 1, wherein the first power supply has a higher energy density than the second power supply.

3. The aerosol generator according to claim 1 or 2, wherein the first power supply is configured to supply power to the controller and any other electronic components of the aerosol generator.

4. The aerosol generating apparatus according to claim 1 or 2, wherein the second power source is a battery having an internal resistance lower than the internal resistance of the first power source.

5. The aerosol generator according to claim 1 or 2, wherein during the first heating stage, the controller is configured to supply power to the electric heater from the second power source.

6. The aerosol generator according to claim 1 or 2, wherein during the first heating stage, the controller is configured to supply power to the electric heater from the first power source and the second power source.

7. The aerosol generator according to claim 1 or 2, wherein during the second heating stage, the controller is configured to supply power to the electric heater from the first power source only.

8. The aerosol generating apparatus according to claim 1 or 2, further comprising at least one electric heater.

9. An aerosol generating system comprising an aerosol generating device according to claim 1 or 2, and at least one electric heater configured to be detachably attached to the aerosol generating device.

10. A method for generating an aerosol in an aerosol generator, wherein the method is This includes supplying electrical energy to at least one electric heater from a first power source and a second power source, The electrical energy from the first power source and the second power source is supplied to the heater simultaneously or at different times. The first power supply and the second power supply are different types of power supplies. The first power source is a Li-NMC, Li-LCO, Li-NCA, or LiPo battery. The second power source is a LiFePO4 battery, The controller supplies power to the heater according to a predetermined heating profile including at least a first heating stage and a second heating stage, wherein different amounts of heating power are supplied to the electric heater in the first heating stage and the second heating stage. The first heating step is a preheating step for preheating the electric heater to its operating temperature, and in the preheating step, power is supplied from a second power source having lower internal resistance and lower energy density than the first power source. The method wherein the second heating step is an operating step used to generate an aerosol that can be inhaled by the aerosol generator, and in the operating step, power is supplied from the first power source having higher internal resistance and higher energy density than the second power source.

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