KR20190032417A - Self-charging and / or self-circulating electrochemical cells - Google Patents

Abstract

The present disclosure provides an electrochemical cell comprising a solid glass electrolyte comprising an alkali metal working ion and a dipole conducted by an electrolyte, an anode with an effective anode chemical potential _{A A} , and a cathode with an effective cathode chemical potential μ _C do. One or both of the cathode and the anode are substantially free of working ions prior to the initial charge or discharge of the electrochemical cell. In an open circuit prior to the initial charge or discharge, the electrical double-layer capacitor is formed on one or both of the interface between the solid glass electrolyte and the anode and the interface between the solid glass electrolyte and the cathode due to the difference between μ _A and μ _C do.

Description

Self-charging and / or self-circulating electrochemical cells

Technical field

This disclosure relates to self-charging and / or self-circulating electrochemical cells containing solid glass electrolytes.

background

An electrochemical cell has two electrodes, an anode and a cathode, separated by an electrolyte. In conventional electrochemical cells, the materials of these electrodes are both electrically and chemically active. The anode is a chemical reductant and the cathode is a chemical oxidant. Both the anode and the cathode can either gain or lose ions, typically the same ion, referred to as the working ions of the battery. The electrolyte is the conductor of the working ion, but generally it can not gain or lose ions. Since the electrolyte is an electronic insulator, it does not allow electrons to move inside the battery. In conventional electrochemical cells, both or both of the anode and cathode contain working ions prior to circulation of the electrochemical cell.

An electrochemical cell operates through a reaction between two electrodes with electronic and ionic components. The electrolyte conducts the working ions inside the cell and also forces the electrons participating in the reaction to pass through the external circuit.

The battery can be a simple electrochemical cell or a combination of multiple electrochemical cells.

summary

The present disclosure provides an electrochemical cell comprising a solid glass electrolyte comprising an alkali metal working ion and a dipole conducted by an electrolyte, an anode with an effective anode chemical potential _{A A} , and a cathode with an effective cathode chemical potential μ _C do. One or both of the cathode and the anode are substantially free of working ions prior to the initial charge or discharge of the electrochemical cell. In an open circuit prior to the initial charge or discharge, the electrical double-layer capacitor is formed on one or both of the interface between the solid glass electrolyte and the anode and the interface between the solid glass electrolyte and the cathode due to the difference between μ _A and μ _C do.

An electrochemical cell may have any or all of such characteristics, unless the following additional features are clearly mutually exclusive: a) at least one or both of the cathode and the anode may comprise a metal; b) at least one or both of the cathode and the anode may consist essentially of or consist of metal; c) both the cathode and the anode are substantially free of working ions prior to the initial charge or discharge of the electrochemical cell; d) one of the cathode and the anode may comprise a metal, consist essentially of a metal, or consist of a metal, and the other may comprise a semiconductor; e) one or both of the cathode and the anode may comprise a catalytic molecule or a particle relay which determines its effective chemical potential; f) Working ions may include lithium ions (Li ⁺ ), sodium ions (Na ⁺ ), potassium ions (K ⁺ ), magnesium ions (Mg ²⁺ ), aluminum (Al ³⁺ ) have; g) the dipole can have the general formula A _y X _z or the general formula A _y-1 X _z ^-q wherein A is Li, Na, K, Mg, and / or Al, X is S and / Or O, 0 < z? 3, y is sufficient to ensure the charge neutral of the dipole of the general formula A _y X _z , or ^-q of the dipole of the general formula A _y-1 X _z ^-q , 1? Q? 3; h) the dipole may comprise up to 50% by weight dipole additive; i) the dipole additive may comprise one of the compounds having the general formula A _y X _z or a compound having the general formula A _y-1 X _z ^-q or a combination thereof, wherein A is Li, Na, K, Mg, and and / or Al, X is S, O, Si, and / or OH, 0 <z≤3, y is the dipole charge neutrality of the additive of the general formula a _y X _z, or the formula a _y-1 X ^q-q of the dipole additive of _z- ^q , and 1? q? 3; j) an electrochemical cell may have a cycle life of at least a thousand cycles; k) the battery may exhibit a discharge current even when it is not receiving energy from an external source at the time of its closing-circuit; l) an electrochemical cell may represent a self-circulating component of charge or discharge current and / or voltage at a fixed control current imposed by an external potentiostat; m) The electrochemical cell can be reversibly and dendritically plated with working ions on the anode during charging; n) an electrochemical cell can exhibit self-charging without controlled charge current; o) the electrochemical cell may exhibit a self-charging current component having a controlled charge current component; p) An electrochemical cell can exhibit a self-charging component without controlled discharge current; q) An electrochemical cell can exhibit self-charging without controlled discharge current; r) electrochemical cells may have a charge / discharge Coulomb efficiency of greater than 100%; s) The electrochemical cell may exhibit a measured charge or discharge current that is less than the control current; t) an electrochemical cell may have a charge current greater than the control current upon charging; u) The electrochemical cell may have a current measured in the opposite direction of the control current; v) the electrochemical cell may have a measured discharge current greater than the control current at discharge and may exhibit self-cycling of both the measured discharge current and voltage; w) the electrochemical cell may exhibit an alternating current having a duration of at least one minute; x) An electrochemical cell may exhibit an alternating current having a duration of at least one day.

The present disclosure further includes a battery comprising one of the electrochemical cells described above, or at least two such cells that may be in series or in parallel.

The electrochemical cells and batteries described above and elsewhere herein can be recharged.

Brief Description of Drawings
BRIEF DESCRIPTION OF THE DRAWINGS For a more complete understanding of the invention and the features and advantages thereof, reference is now made to the following description taken in conjunction with the accompanying drawings, in which: FIG.
1A is a schematic cross-sectional view of an electrochemical cell according to the present disclosure prior to a first charge in an open circuit.
1B is a schematic cross-sectional view of the electrochemical cell of FIG. 1A during self-charging.
1C is a schematic cross-sectional view of the electrochemical cell of Figs. 1A and 1B during discharge.
Figure 2 is a schematic diagram of an equivalent circuit that can be used to calculate the time dependence of the evolution of the voltage measured in the open circuit of the electrochemical cell of Figure la.
Figure 3a-3d are a series of graphs of test results for the Al-C anode, Li ⁺ electrochemical cell having a solid electrolyte containing glass SC-Cu cathode and 10% Li ₂ S. The measured voltage is denoted _Vme (t). The measured current is indicated by _Ime (t). Control current is represented by I _con (t) is a -1 μ _A versus time (t) after a short-time charge (vertical line on the left side in Fig. 3a). Figure 3a shows the results for an electrochemical cell that can self-circulate without circulation for 41 hours and self-circulate for 27 hours with a circulation period of about 8 minutes following self-charging. Figure 3b shows an enlarged time-scale graph of 40 to 42 hours during the period of the graph of Figure 3a. Figure 3c shows the results from the second cycle of the electrochemical cell of Figures 3a and 3b after the second short-time charge, while the electrochemical cell starts at 20.5 hours and is heated from 12 占 to 22 占 for a 2 hour period, . Figure 3d shows an expanded time-scale graph during the period of the graph of Figure 3c while electrochemical electricity is being heated.
4 is a graph of discharge voltage versus time measured after closing the circuit of an electrochemical cell with a Li anode, a C-Ni mesh cathode, and a Li ⁺ solid glass electrolyte. The self-circulation cycle is 24 hours.
Figure 5a is a graph of test results for the Al-C anode, Li ⁺ electrochemical cell having a solid electrolyte containing glass SC-Cu cathode and 10% Li ₂ S. The measured voltage is denoted _Vme (t). The measured current is indicated by _Ime (t). The control current is denoted I _con (t) and is 0.2 mA during charging and -1 _A during self-charging. Figure 5b shows the magnified current axis for a portion of the graph of Figure 5a.
Figure 6 is a graph of the first discharge current versus time measured after closing the circuit of a jelly roll electrochemical cell with Al-C anode, Cu cathode, and Li ⁺ solid glass electrolyte. The discharge occurred with low load resistance.
7 is a Li anode, γMnO ₂ -C-Li glass -Cu cathode, and Li ⁺ is a graph of the voltage versus time measured for 5 hours, charge / discharge cycle 5 times for an electrochemical cell having a solid electrolyte glass. The electrochemical cell was cycled for 190 days. The peak voltage is indicated by an arrow.

details

The present disclosure is directed to an electrochemical cell comprising a solid glass electrolyte capable of reversibly plating working ions on an electrode containing an operating ion as well as an electrical dipole and not re-supplied by another electrode, Resulting in an electrochemical cell exhibiting self-charging and self-circulating behavior. The cell typically has a solid electrolyte containing a mobile alkali metal working cation that can be plated without a dendrite on the metal current collector as well as a molecular electrical dipole that moves more slowly. The difference in electrochemical potentials of the two electrodes is the driving force to create an electric-double-layer capacitor at each electrode / electrolyte interface, as in an ordinary electrochemical cell, in an open circuit. However, the translational mobility of the working cation and the difference in orientation and translational mobility of the electric dipole slows any excess charge formation in the electrolyte at the interface. The dipole contribution to interfacial charge can be large enough to induce plating of the working cation as an alkali metal-layer on the anode, which represents self-charging . If the counter electrode can not re-supply the last working cation from the electrolyte via such self-plating or applied charge power, the electrolyte is negatively charged until it reaches the plane between plating and peeling. The charge of the electrolyte is represented by an equivalent circuit as an inductor in parallel with the capacitor, which can produce a self-circulating component of charge or discharge current and / or voltage at a fixed control current imposed by the external potentiostat.

The electrolyte is referred to as glass because it is amorphous as can be confirmed by X-ray diffraction. The working ion may be an alkali-metal cation such as Li ⁺ , Na ⁺ , K ⁺ , or a metal cation such as Mg ²⁺ and / or Al ³⁺ .

Self-charging is a phenomenon in which an electrochemical cell contains an electrode that does not contain the working ions of the cell at the time of manufacture but delivers a discharging current even when the charging current is not received from an external source when the external circuit is closed Quot; This phenomenon is the result of the electric dipoles being aligned and displaced in the electrolyte after cell assembly as a result of dipole-dipole interaction and internal electric field. The internal electric field provided by the dipole alignment is large enough to galvanize the electrolyte negatively by plating the working ion as one of the metals from the electrolyte into one of the electrodes without re-supplying the working ions from the other electrode to the electrolyte. When the external circuit is closed, the working ions return to the electrolyte, and the electrons are sent to an external circuit that provides the discharging current.

Self-circulation occurs when the working ions of the electrolyte are plated onto the electrode, which negatively charges the electrolyte. When the negative charge of the electrolyte is large enough, the plated metal is peeled back into the electrolyte as a cation and the electrons are released to the external circuit. The different reaction rates of the dipole and the ions and electrons of the electrolyte to the external circuit cause the circulation of current in the external circuit and / or the cell voltage.

Both self-charging and self-circulating behavior can occur without external energy input, but both phenomena can also occur as a component of battery charge / discharge performance through external charge / discharge inputs. For example, a self-charging electrochemical cell may be provided with a charging current as an external energy input, which in this case will represent a greater charge than indicated by the charging current to provide a coulombic efficiency of greater than 100%. As another example, the discharge current and / or voltage may have a self-cycling component at a frequency that is different from the charge / discharge cycle frequency.

The solid glass electrolyte of the present disclosure is nonflammable and is capable of plating a dendritic-free alkali metal on the electrode collector and / or itself; The atoms of the plated metal come from the working ions of the electrolyte; The plated working ions may or may not be re-supplied to the electrolyte from the other electrode. In particular, the solid electrolytes of the present disclosure may include, as working ions, alkali metal cations such as Li ⁺ , Na ⁺ , K ⁺ , metal cations such as Mg ²⁺ , Al ³⁺ as well as electric dipoles, For example, A ₂ X or AX ^- , or MgX or Al ₂ X ₃ , where A is Li, Na, or K, and X is O or S or another element or dipole molecule . Suitable A ^{&lt; +} & gt ^{; -type} glass electrolytes and methods for their preparation have already been described in WO2015 128834 (Water Solvated Glass for Lithium or Sodium Ion Conduction) and W02016205064, Metal-ion descriptions are incorporated by reference therein.

Generally, the metal working ion in the solid glass electrolyte used in the electrochemical cell of this disclosure may be an alkali-metal ion, such as Li ⁺ , Na ⁺ , K ⁺ , or Mg ²⁺ or Al ³⁺ ; Some of these transferable working ions may also be attached to anions to form electric dipoles with less mobility, such as A ₂ X, AX ^- , or condensates thereof with larger ferroelectric molecules where A is Li , Na, K, Mg, Al, and x is O, S, or other anion atoms. The glass may also contain up to 50 weight percent of other electro-dipole molecules as additives than those formed from precursors used in glass synthesis without dipole additives. The presence of electrical dipoles provides a high dielectric constant to the glass; Dipoles are also active in promoting self-charging and self-circulation phenomena. In addition, the solid glass electrolyte is not reduced upon contact with metallic lithium, sodium, or potassium and is contacted with a high voltage cathode such as spinel Li [Ni _0.5 Mn _1.5 ] O ₄ or olivine LiCo (PO ₄ ) and LiNi (PO ₄ ) . Thus, a passivated solid-electrolyte intermediate phase (SEI) is not formed. In addition, the surface of the solid-glass electrolyte is wetted by alkali metal, which provides low resistance to the transfer of ions across the electrode / electrolyte interface for at least 1,000, at least 2,000, or at least 5,000 charge / discharge cycles Allows plating from glass-electrolyte dendrite-free alkali metals.

The solid glass electrolyte can be applied as a slurry over a large surface area; The slurry may also be incorporated into paper or other flexible cellulosic or polymeric membranes; Upon drying, the slurry forms a glass. The membrane framework may have attached electrical dipoles or, upon contact with the glass, form electrical dipoles with only rotational mobility. Electric dipoles in glass can have rotational mobility as well as translational mobility at 25 캜. The reaction between dipoles with translational mobility can form a dipole-rich region in the glass electrolyte with some dipole condensation into the ferroelectric molecule; Adhesion of the dipoles, referred to as aging of the electrolyte, can take several days at 25 占 폚, but can be accomplished within a few minutes at 100 占 폚.

One or more of the dipoles may have some mobility even at 25 占 폚. The electrode comprises a current collector and / or a material having an active redox reaction. The electrode collector is an excellent metal such as Al or Cu; It can also be in the form of carbon, alloys, or compounds such as TiN or transition metal oxides. The current collector may be an electrode on which there is no active material or it may transport electrons from / to the active material on it; The active material may be an alkali metal, an alloy of an alkali metal, or a compound containing atoms of the working ions of the electrolyte. The current collector transports electrons to and from the external circuit or from the active material of the electrode or from the active material and reacts with the working ions of the electrolyte through electronic contact with the current collector and ionic contact with the electrolyte. Ionic contact with the electrolyte may only include an excessive or insufficient working-ion concentration at the electrode / electrolyte interface, which produces an electro-double-layer capacitor (EDLC), or it may also involve chemical formation at the electrode surface have. In a rechargeable battery, any chemical formation on the electrode surface as well as the EDLC across the electrode / electrolyte interface is reversible.

According to the present invention, one or both electrodes of an electrochemical cell is the only current collector that does not contain, at the time of manufacture, less than 7000 ppm of detectable atoms of the working ions of the electrolyte, for example, by atomic absorption spectroscopy . However, after battery assembly, the atoms of the working ions of the electrolyte can be detected on the electrodes by atomic absorption spectroscopy or other means.

In addition, one or both electrodes of the cell may contain additional electron conductive material such as carbon that does not significantly alter the effective Fermi level of the composite current collector and that helps to coat the working cation on the current collector.

The solid glass electrolyte may have a large dielectric constant such as a relative dielectric constant ( _R ) of 10 ² or more. The solid glass electrolyte is nonflammable and can have an ionic conductivity, _A , of at least 10 &lt; ^-2 & gt ^; S / cm at 25 DEG C for the working ion A ⁺ . This conductivity is similar to the ionic conductivity of a conventional non-flammable organic-liquid electrolyte used in Li-ion batteries to make the cell safe.

The solid glass electrolyte is produced by transforming a crystalline electronic insulator containing an actinic ion or its constituent precursor (typically containing an actinic ion bound to O, OH and / or halide) into an actinic-ion-conducting glass / amorphous solid . This process can also take place in the presence of dipole additives. The working ion-containing crystalline, electronic insulator or composition precursor thereof can be a material having the general formula A _3-x H _x OX, wherein 0? X? 1, A is at least one alkali metal, X is At least one halide. Water can escape the solid glass electrolyte during its formation.

An electrochemical cell containing the solid glass electrolyte disclosed herein can have a large energy gap E _g , where E _g = E _e - E _v . E _c is the bottom of the conduction band and E _c > μ _A , where μ _A is the anode chemical potential. E _v is the top of the valence band and E _v <μ _C , where μ _C is the cathode chemical potential. The energy difference μ _A -μ _C can lead to self-charging and self-circulating behavior. In addition, the contribution of the dipole causes the electrochemical cell to have higher capacitance in otherwise identical electrochemical cells having electrolytes other than the solid glass electrolytes disclosed herein in an open or closed circuit.

The electrochemical cell containing the solid glass electrolyte disclosed herein may also be capable of plating and stripping working ions from one or both electrodes such that the electrolyte-electrode bond between the electrolyte and the at least one electrode is changed Strong enough to be substantially perpendicular to the interface between the electrolyte and the electrode. Typically, the bond between the electrolyte and both electrodes will be strong enough so that the electrolyte volume change is substantially perpendicular to both the electrolyte and both interfaces between the electrodes.

In the following, the control current I _con is the current specified by the potential difference between the two electrodes controlled by the load of the potentiostat, whereas the measured current I _mc is the current specified by the potentiostat and the current Is the actual measured current including the current. The current due to self-charging may be the same or opposite to I _con at discharge. The subscripts dis and ch are added to specify whether the inventors represent discharge or charge current and voltage.

The electrochemical cell disclosed herein may have a measured discharge current I _me-dis less than the control current I _con and / or a measured charge current I _me-ch .

During charging, the electrochemical cell disclosed herein may have a charge current I _ch that is greater than the control current I _con . During discharging, the electrochemical cell disclosed herein may have a measured discharge current I _me-dis greater than the discharge control current I _dis-con . Such an electrochemical cell may exhibit self-circulation of both the measured discharge current I _me-dis and the voltage V _me-dis in addition to the steady discharge.

The electrochemical cell disclosed herein can generate a voltage that is less than or equal to the theoretical voltage as a result of the difference in electrode electrochemical potential, in an open-circuit.

The electrochemical cell disclosed herein may have a self-voltage large enough to allow the working ions in the electrolyte to be plated on the anode in an open-circuit. Moreover, the power delivered by self-charging may be sufficient to turn on the red LED for more than one year.

The electrochemical cell disclosed herein may exhibit plating of ions on any electrode collector when applied to a constant I _con or V _con . Plating of the working cation from the electrolyte without re-feeding by the counter electrode can generate the self-circulating component of the measured current I _me and the measured voltage V _me .

In the following, the control current I _cm is the current specified by the potential difference between the two electrodes controlled by the load of the potentiostat, while the measured current I _me is the current specified by the potentiostat and the current Is the actual measured current including the current. The current due to self-charging may be the same or opposite to I _con at discharge. The subscripts dis and ch are added to specify whether the inventors represent discharge or charge current and voltage.

The electrochemical cell disclosed herein can exhibit self-cycling in a given cycle time. Due to self-charging, the period of self-circulation is independent of the charge / discharge period.

The measured current of the electrochemical cells described herein _me I includes both DC and AC components. In some applications, only the AC portion can be used, for example, in signaling. The exchange period is a self-circulation period that can have a period of several minutes to several days.

1, which illustrates an electrochemical cell 100 prior to circulation; FIG. 1 a is a cross-sectional view of an electrochemical cell 100 during self-charging; FIG. And FIG. 1C illustrating electrochemical cell 100 during discharge.

1A, 1B and 1C, an electrochemical cell 100 includes an anode 10 having a contact portion 15, a cathode 20 having a contact portion 25, and a solid alkali-metal-ionic glass electrolyte 30). Excessive working ions in the electrolyte 30 are indicated by a + circle. The depletion of working ions in the electrolyte 30 is indicated by a circle. The electric dipole of electrolyte 30 is denoted +/- oval. The electron charge of the electrode is represented by the + and - circles. In Figures 1B and 1C, the arrows in the circles indicate the charge associated with the excess of mobile cations or lack of mobile cations in the electrolyte, the direction of movement of electrons in the electrode.

FIG. 1A schematically illustrates an electrochemical cell 100 in an open-circuit. The chemical potential ( _A ) of the anode (10) is higher than the chemical potential ( _C ) of the cathode (20). Electrical double-layer capacitors 40a and 40b are formed at the interface between the electrode and the electrolyte to balance the energy between the anode and cathode chemical potentials. The energy for forming these electrical double-layer capacitors 40a and 40b is supplied by the difference in the chemical potentials of the anode 10 and the cathode 20. [

One such electrochemical cell 100 has an alkali-metal working ion (A ⁺ ) in the solid glass electrolyte 30 and may have an alkali metal anode 10 and a Cu cathode 20.

The displacement of the working ion (A ⁺ ) and electric dipole in the solid glass electrolyte 30 can form electrical double-layer capacitors 40a and 40b. The electric double-layer capacitor 40a at the interface of the anode 10 (which is the negative terminal of the electrochemical cell 100) and the electrolyte 30, in the open circuit, (Indicated by +) within the electrolyte 30 as a result of the working ion of the working electrode moving toward its anode side. The portion of the anode 10 at the interface will have an excess negative negative electron charge (denoted by -) and an excess positive positive cation charge on the electrolyte side of the interface between the anode 1 and the electrolyte 30, .

The electric double-layer capacitor 40b at the interface of the cathode 20 (which is the positive terminal of the electrochemical cell 100) and the electrolyte 30 is electrically connected to the working electrode of the electrolyte 30 toward its anode and its cathode side (Indicated by -) in the electrolyte 30 as it moves away from the electrolyte 30. A portion of the cathode 20 at the interface will have a compensating excess of positive electron charge at the cathode 20 remote from the interface with the electrolyte 30 (marked +).

In addition to the interface with the electrode whose charge changes as described above, the electrolyte 30 will have neutral net charge.

Once the electrochemical cell 100 is assembled, the movement of the working ions of the electrolyte 30 and the formation of the resulting electrical double-layer capacitors 40a and 40b occurs quite rapidly.

Due to the resulting electric field in the direction of balancing the movement of the working ions within the electrolyte 30 and the difference in the electrochemical potentials of the two electrodes, the electric dipole in the solid glass electrolyte is shown as an indicator of + and - There will tend to orient themselves such that their negative ends point at the interface between the electrolyte 30 and the anode 10 and their positive ends face the interface between the electrolyte 30 and the cathode 20 .

The alignment of these electrical dipoles and their translational motion do not occur instantaneously and are a significantly slower process than the formation of electrical double-layer capacitors 40a and 40b. As a result, the open circuit voltage (Voc (t)) measured over time evolves as alignment and dipole translations occur. The development of this Voc (t) can be modeled using an equivalent circuit as shown in the schematic diagram of Fig. The schematic diagram of FIG. 1A shows a hypothetical electrochemical cell 100 in which the dipoles within the solid glass electrolyte 30 are all aligned and displaced. In practice, complete alignment and displacement will not be achieved and dipole translational and alignment will increase as Voc (t) develops. The increased dipole alignment also enhances the electric field across the electrolyte 30 and further induces dipole alignment and movement. The maximum alignment and movement in a given electrochemical cell 100 may be achieved by varying V _oc over time, or for a given period of time, e.g., for at least 1 minute or at least 5 minutes for alignment, It can be assumed that it occurred for a few minutes when it stopped changing in a consistent direction.

In some cases, the additional electric field generated by dipole alignment and movement in the electrolyte 30 may be sufficient to induce plating of the working ions on the anode 10 even when the electrochemical cell 100 is in an open-circuit have. As a result, the net negative charge generated by the electrolyte 30 as a result of this plating process will be sufficiently high that the electric field can not be overcome and plating on the anode 10 will stop.

1B shows the electrochemical cell 100 when the circuit is first closed, for example by connecting an external circuit to the contacts 15 and 25. The external circuit includes a potentiostat that imposes a charge control current, I _con , which may be less than some critical current I _c . The threshold current is the maximum I _{con-dis at} which the self-charging phenomenon still exists as shown in FIG. 1B. When the circuit is closed, the energy stored by the aligned dipoles of the electrolyte 30 in the electric double-layer capacitors 40a and 40b introduces the charging current I _ch . This phenomenon self-charges the electrochemical cell 100.

During self-charging, some electrons are transported from the cathode 20 to the anode 10, while the discharge control current I _con is applied, where they are transported to the anode 10 by an excess of working ions in the electrolyte 30 And then the anode 10 is plated to form a plated metal 50.

The cathode 20 lacks working ions and can not re-supply working ions as they become depleted from the electrolyte 30 to form the plated metal 50. Thus, the electrolyte 30 at the interface with the anode 10 is increasingly negatively charged, and eventually the working ions are no longer plated on the anode 10 as the plated metal 50 and the working ions are stripped back to the electrolyte It reaches the point of starting.

Alternatively, the plated metal may be thickened so that the electrode chemical potential becomes the potential of the plated metal rather than the current collector, 10, which makes it more difficult for the working cation to be plated from the electrolyte as metal 50, Lt; / RTI &gt; In any case, as the plating of the working ions to the anode 10 decreases, the measured charging current I _me-ch decreases.

Further, the initial former is removed from the cathode by the electric double charging current I _ch - to move the dipole orientation of a layer 70 which may have a capacitor (40b), towards the cathode (20). However, the working ions in the electrolyte 30 do not move to the cathode 20.

As a result, depletion of working ions from the electrolyte 30 near the anode 10 induces its dissociation from the plated metal 50 back to the electrolyte 30 in the discharging step, and I _me-ch is further reduced And electrical double-layer capacitors 40a and 40b are recovered (not shown). As a result, the energy stored in the electrical double-layer capacitors is sufficiently high that further depletion of the working ions from the plated metal 50 can not contribute enough still further energy to occur and the operation on the anode 10 as plated metal 50 Plating of ions resumes, increasing I _me-ch .

Although the above description refers to plating and delamination in a simple manner, which occurs at any time, in an actual electrochemical cell 100, both plating and delamination occur simultaneously during at least a portion of each cycle, but one process predominates There is plating or pure delamination.

This change between the pure plating and the pure separation of the working ions from the plated metal 50 on the anode 10 causes the self-circulation of the electrochemical cell 100 with the simultaneous circulation of the voltage V. Such self-cycling occurs during a given cycle period and tends to remain constant as long as the cycle continues. The cycle duration depends on the difference in the rate of electron-to-cation and dipole translational motion.

In an electrochemical cell 100 such as the electrochemical cell of FIG. 1B, where I _con is less than I _c , the cycle duration may be in units of several minutes between one and ten minutes.

Fig. 1C shows a circuit diagram of an embodiment of the present invention through an external circuit comprising a potentiostat which imposes a control current I _con greater than the threshold current I _c , such as, for example, in a low-load external circuit that may include a light emitting diode An electrochemical cell 100 during discharge. As with the electrochemical cell of Figure Ib, once the circuit is closed, energy is stored by the aligned dipoles of electrolyte 30 in electrical double-layer capacitors 40a and 40b.

During discharging, current I _dis is generated and can be controlled by I _con . The load of the external circuit is sufficiently low to allow electrons to flow from the anode 10 to the cathode 20 so that the working ions are drawn from the electrolyte 30 to the cathode 20 where they are combined with electrons, To form a metal (60). The transfer of electrons from the anode 10 to the cathode 20 reduces both the electrical double-layer capacitors 40a and 40b, but mainly at the electrolyte-cathode interface, the electrical double-layer capacitor 40b. This lowers the electric field across the electrolyte 30, causing the working ions to be plated on the cathode 20. The electrical double-layer capacitor 40b is exhausted, but this is typically not destroyed so long as most of the dipoles of the electrolyte 30 are still oriented in the same manner as when the electrochemical cell 100 is in the open circuit. However, the dipole of the electrolyte 30 is compressed in the direction 80.

The anode 10 is substantially free of working ions and can not re-supply them when the working ions are depleted from the electrolyte 30 to form the plated metal 60. In addition, changes in the internal electric field of the electrolyte 30 produced by electron transfer that occur much faster than working ions and electric dipoles can be redistributed and aligned to accommodate them. Thus, the electrolyte 30 at the interface with the cathode 20 is gradually and negatively charged, and eventually reaches the point at which the working ion also peels from the plated metal 60 and returns to the electrolyte 30, the equilibrium until achieve generates a gradually lower the measured discharge current I that is _me until it reaches a minimum value I _me.

Alternatively, in some electrochemical cells 100, the plated metal 60 may ultimately become very thick, the electrolyte 30 is effectively screened from the cathode 20, and the working ions in the electrolyte 30, Substantially all of the plated metal 60 does not have a sufficient difference in chemical potential compared to the electrode 10 so that only the difference in chemical potential or the additional plating of the electrolyte 30, &Lt; / RTI &gt; In such a case, the working ions may no longer be plated on the cathode 20 as the plated metal 60.

I _me is increased because the ion plating operation metal 60. When _Ime reaches a maximum, the process is reversed and working ions are again plated on the cathode 20 as a metal plate 60.

These changes between the metal 60 is plated, and the separation of the ion plating operation on on the cathode 20 with the simultaneous circulation of the voltage and I _me, characters of the electrochemical cell (100) to generate a circulation. This self-cycling occurs during a given cycle period, which tends to remain constant as long as the cycle continues. Cycle periods are dependent on the compression rate in the direction 80 of the dipole in the electrolyte 30 during discharge and their expansion during charging. Typically, _maximizing I _me is faster than minimizing it.

In an electrochemical cell 100 such as the electrochemical cell of FIG. 1C, if I _con is _greater than I _c , the duration may be in days or days between one and seven days.

The electrons can only pass in one direction through the LED. Thus, in practical use of the electrochemical cell 100, the anode 10 is increasingly positively charged and the cathode 20 is increasingly negatively charged until the electric field across the electrolyte 30 reverses the orientation of the electric dipole. And then cut off the current flowing through the load. For electrochemical cells with small I _me , the time required for this phenomenon to take place can be long and may even take another year. Thus, the electrical device can be powered by the electrochemical cell 100 for the length of time without external energy input.

In an electrochemical cell 100 that is substantially free of working ions on both electrodes before assembling the cell, the external charging current I _ch can produce large electrical double layer capacitors 40a and 40b, Such as occurs during charging of a conventional rechargeable electrochemical cell. Unlike conventional rechargeable electrochemical cells where such recharging occurs, however, depletion of working ions from the electrolyte 30 without re-feeding from the cathode 20 results in negative charge of the electrolyte 30 near the anode 10 Resulting in increased resistance to further plating on the anode 10. Further, the change in the electric field of the entire electrolyte 30 due to the acceptance of molecules and atoms in the electrolyte that is slower than the electron movement in the current collector changes the rate of self-charging and self-circulation. Therefore, as in the case of the electrochemical cell shown in Fig. 1B, the separation of the working ions from the anode 10 also occurs. As a result, in a constant control external charge current I _con-ch , an equilibrium is achieved between plating and exfoliation of working ions in the anode 10.

In such an electrochemical cell, the measured charge current I _me-ch is greater than a constant controlled external charge current I _con-ch because the electrical double-layer capacitors 40a and 40b, in addition to being plated and stripped, Because it is charged. Also, the measured charging voltage V _me-ch and the measured charging current I _me-ch vary periodically with time as plating and peeling progress.

In such a cell, the average I _me-ch may be greater than or equal to I _con-ch while the working ions are stripped from the anode 10 and plated with the anode 10. When plating / peeling in the anode 10 is continued, the electric double-layer capacitor 40a near the anode 10 is also charged. As a result, the electric double-layer capacitor 40a is sufficiently charged with negative charges on the anode side to block the return of electrons to the anode 10, thereby preventing additional detachment of working ions from the anode 10. [ At this time, the subsequent charge can only charge the electrical double-layer capacitor 40a. As a result, the self-circulation of the voltage stops and the voltage increases linearly with time at a rate dependent on I _con-ch .

In a variant, if the working ions are plated on the cathode 20 before the external charging current is applied, the measured discharge current I _me-dis is self-circulated until the working ions are substantially separated from the cathode 20 . However, the measured discharge voltage V _me does not circulate.

추진력이다.In Fig. 2, the inductance is introduced into the equivalent circuit and represents the role of negative charge introduced into the electrolyte 30 by plating the working cations from the electrolyte without re-supplying from the counter-positive to the electrolyte. In Figure 2, C represents the combined capacity of a series of 40a and 40b EDLC, R _L represents the plating resistance,

It is propulsion.

The electrochemical cell of the present disclosure can be used in a battery. Such a battery may be a simple battery that contains fewer components than electrochemical cells and casings or other features. Such a battery may be a standard battery type such as a coin cell, a standard jelly roll, a pouch, or a prismatic cell type. These may be more customized types, such as custom prism cells.

The electrochemical cells of this disclosure may be used in more complex batteries, such as batteries that include complex circuits and processors and memory computer-implemented monitoring and regulation.

Regardless of simplicity, complexity, or type, all batteries using the electrochemical cells of this disclosure can exhibit improved safety, especially when touched, as compared to cells having an organic-liquid electrolyte Can be less.

The battery may comprise a single electrochemical cell as disclosed herein, or two or more such cells that may be connected in series or in parallel.

The electrochemical cells and batteries containing them disclosed herein may be rechargeable.

The electrochemical cell of the present disclosure can be used in devices that use electrical double-layer capacitors, such as in capacitors. They can also be used in devices that use cycle periods, especially AC periods such as signaling devices.

By way of example, the electrochemical cell of the present disclosure is a dielectric gate of a field-effect transistor; In portable, compact and / or wearable electronic devices such as telephones, watches, and laptop computers; In fixed electronic devices such as desktop or mainframe computers; In an electric tool such as a power drill; On electric or hybrid aviation, land or water transport means such as boats, submarines, buses, trains, trucks, cars, motorcycles, mopeds, powered bicycles, aircraft, drone, other flying vehicles, and toy forms thereof; For other toys; For energy storage, for example, as a fixed power store for small-scale use, such as power storage and / or grid storage from wind, solar, hydropower, or nuclear power, or in the case of a home, workplace, or hospital; For sensors such as portable medical or environmental sensors; To generate low frequency electromagnetic waves such as underwater communications; As a capacitor, for example, in a supercapacitor or a coaxial cable; Or as a transducer.

Example

The following examples are provided to further illustrate the principles and specific embodiments of the invention. They are not intended to and should not be construed as encompassing the full scope of all aspects of the present invention.

Example 1 - In an electrochemical cell I _con  <I _c

Figure 3 shows the results of an experiment demonstrating self-charging and self-circulation of an electrochemical cell with an Al-C anode, a SC-Cu cathode and a Li ⁺ solid glass electrolyte containing 10 wt% Li ₂ S (Al- C / Li ⁺ - glass / SC-Cu battery).

The Al anode had a carbon layer (Al-C) in contact with the Li-glass electrolyte. The cathode was a Cu current collector having a carbon layer containing a sulfur relay in contact with the Li-glass electrolyte.

In Figure 3a, the measured voltage of the electrochemical cell over time showed a charge of 0.5 mA for 25 minutes after 6 hours and 26 minutes, followed by a sudden discharge of electrical double-layer capacitors. Electrical double-voltage of the constant I _con As layer capacitor is then recharged did not substantially increase for 8 hours 22 minutes, then after less for 35 hours 29 minutes was increased to 2.4 V to the amplitude noise. The measured voltage of 2.4 V, V _me , was the maximum voltage for the self-charging plating of the lithium metal Li ⁰ on the anode. Before the start of the vibration, a short break of the voltage increase rate occurred when V _me was 2.2 V. The theoretical V _me for (μ _A -μ _C ) / e was 2.2 V. If the thickness of the plating on the Al-Li ⁰ C anode reaches a critical thickness, the plating / stripping of Li ⁰ is in _{μ A (Li) -μ C (} Cu) and _{μ A (Al) -μ C (} Cu) Of the plating.

Figure 3b between the characters is also measured at the _{3a [μ A (Li) -μ} C (Cu)] / e and _{[μ A (Al) -μC (} Cu)] / e - A magnified image of the start of cycle And the vibration can be seen more clearly.

Figure 3c is a second cycle at a constant I _con after the initial charge of Co ₂ mA for 25 min shows a V _me of the cell of Figure 3a. During self-charging, Li ⁺ from the glass electrolyte after charging of the electrical double-layer capacitor was plated on the Al anode, and Li ⁺ working ions were not re-supplied from the Cu cathode to the electrolyte. As can be seen in the 1.65 V to add when, in the enlarged 3d reaches V _me, who in V _me average of about 1.7 V - it was circulated to start.

By heating at 12 ℃ to 26 ℃ Sikkim occurred a rapid deterioration of the V _me when increasing the temperature of the electrochemical cell. Thereafter, the electrochemical cell was removed from the heater and slowly returned to 12 deg. During cooling, V _me was increased to the 2.1 V difference in the chemical potential of Al and Cu. At that voltage, the electrochemical cell began to re-coat the working ions until a small discharge occurred, but there was no periodic circulation followed by long-term circulation; The discharge of the capacitor layer took place - electric double to approximately 1.4 V of V _me. At that point, plating was resumed. Throughout this voltage change, the measured charging current I _me was kept substantially constant, there was a small reduction for only a sudden shut down the final coating at the time of the last write discharge. Temperature-dependent changes reflect ionic and molecular motion of the electrolyte.

Example 2 - In an LED-containing external circuit, I _con  > I _c

An electrochemical cell having an Al anode, a Cu cathode, and an electrochemical cell (Al / Li ⁺ - glass / Cu battery) having a Li ⁺ solid glass electrolyte was then connected in series to turn on the red LED in an external circuit. These cells exhibited self-charging to a discharge current I _dis greater than the critical current I _c . The electrochemical cell was previously circulated, but was not charged or otherwise supplied with external energy input. The battery powered the LEDs for about two years. Data per cell for the first year are presented in Table 1. The total energy density delivered in the first year was 373.8 Wh / g.

Table 1 - Al / Li for one year by LED-containing external circuit ⁺ - Glass / Cu battery

Example 3 - In an electrochemical cell having a Li anode, I _con  > I _c

Figure 4 shows the measured voltage V _me (t) of a discharge electrochemical cell with Li metal anode, Li ⁺ glass electrolyte and C-Ni cathode with carbon located in the Ni mesh (Li-metal / Li ⁺ / C-Ni battery). Load resistance is 1 megohms (mega ohm) and the discharge current is about 2.5 μ _A. Periodic hillock at the voltage was the result of cyclic self - cycling of the self - charged components in the battery discharge compound. Plating on the cathode had a longer period of time than plating on the anode (as shown in Figure 3B). Due to the excess energy supplied by the self-charging, the electrochemical cell showed a charge / discharge coulombic efficiency of more than 100% in circulation.

Example 4 - Constantly Applied Charge Current (I _con-ch )> I _c

Figure 5a is a second charge / Al-C, as the discharge is used in the practice of the cycle Example 1 / Li ⁺ - glass / in SC-Cu cell constant charging control current (I), in which a charging current measurement to the _con-ch I _me-ch Circulating &lt; / RTI &gt; The battery was recharged by an external power source after the first discharge. The measured voltage (V _me) was 2.1 V, which corresponds to _{[μ A (Al) -μ C} (Cu)] / e. I _con as larger _{me I-ch} is shown in Figure 5b, _{I-ch me} the self having an amplitude such that significant maintenance than I _con - shows the circulation.

I _me-ch is there is significant maintenance than I _con-ch, which short, any possible re-supply of Li ⁺ party from the anode because it is longer than the cycle time, which is caused due to the electrolyte charged limited to interface between the electrolyte and the cathode The plating / peeling cycle indicates that the separation of lithium metal from the cathode contributed to the I _me-ch . The average I _me-ch was maintained constant until most, if not all, of the lithium metal was stripped from the cathode and charging of the cathode electrical double-layer capacitor started. Corresponding to the cycle V _me did not exist since the circulation phenomenon has been limited to the cathode / electrolyte interface.

Example 5 - Jelly-roll electrochemical cell I _dis  > I _c

It shows a roll-C Al / Li ⁺ the measured discharge current I _me of glass / Cu cell - Figure 6 is similar to jelly, unlike Example 2, with R _L small load resistance of 0.1 Ω. In the open-circuit, the cathode electrical double-layer capacitor depleted Li ⁺ of the electrolyte at the interface between the electrolyte and the cathode. When the circuit is closed, the electrons from the anode carry negative charges to the Cu cathode, which pulls Li ⁺ back to the cathode interface. However, because the ion mobility is slower than the electron mobility, had I _me again increasing the moving speed of the Li ⁺ to the cathode / electrolyte interface. Threshold electrolyte / cathode electric double-layer capacitor in the voltage, Li ⁺ from the electrolyte is a lithium metal was plated onto the cathode, I _me was abruptly dropped. Subsequent reconstitution of the cathode / electrolyte electrical double-layer capacitor took more time as the negative electrolyte charge again delayed Li ⁺ migration to the cathode / electrolyte interface where plating occurs.

Example 6 - Charge / discharge cycle of an all-solid-state lithium electrochemical cell

7 is a time to circulate an electrochemical cell having an anode Li, Li ⁺ glass electrolyte, and MnO ₂ -C-Li- glass -Cu cathode having a catalyst γMnO ₂ relay on the carbon layer contacting the Cu current collector and charge It shows a change with time of the discharge voltage (Li / Li ⁺ - glass / MnO ₂ -C-Cu cell). Each cycle was 10 hours and 30 minutes for 444 cycles at a control current I _con of 70 _A and a measured discharge current I _me at 53 _A.

Less than I _me I _con is being opposed to the discharge I _con - indicates the presence of the charging current. V _me the profile of a large excess over the peeled from the cathode material in the electrolyte supplied to the plating on the anode Li ⁺ through the self-I showed the typical cycle of the filling. The discharge voltage profile also showed a long cycle period of 34 days.

It is intended that the disclosure be considered as illustrative and not restrictive, and that the appended claims are intended to cover all such modifications, enhancements, and other embodiments that fall within the true spirit and scope of the disclosure. Accordingly, to the maximum extent permitted by law, the scope of this disclosure should be determined by the broadest permissible interpretation of the following claims and their equivalents, and should not be limited or limited by the foregoing description.

Claims (24)

A solid glass electrolyte comprising an alkali metal working ion and a dipole conducted by an electrolyte;
An anode having an effective anode chemical potential _{A A} ; And
An electrochemical cell comprising a cathode having an effective cathode chemical potential, 占_C ,
One or both of the cathode and the anode being substantially free of the working ions prior to the initial charge or discharge of the electrochemical cell,
In the open-circuit prior to initial charging or discharging, an electric double-layer capacitor, one of the interface between the surfactant and the solid glass electrolyte and the cathode between the solid glass electrolyte and the anode due to the difference between μ _A and μ _C or Lt; RTI ID = 0.0 &gt; electrochemical &lt; / RTI &gt; The electrochemical cell of claim 1, wherein at least one or both of the cathode and the anode comprises a metal. The electrochemical cell of claim 1 wherein both the cathode and the anode are substantially free of working ions prior to an initial charge or discharge of the electrochemical cell. The electrochemical cell of claim 1, wherein one of the cathode and the anode is a metal and the other comprises a semiconductor. The electrochemical cell of claim 1, wherein one or both of the cathode and the anode comprises a catalytic molecule or a particle relay for determining its effective chemical potential. The method of claim 1, wherein the working ion is selected from the group consisting of lithium ion (Li ⁺ ), sodium ion (Na ⁺ ), potassium ion (K ⁺ ), magnesium ion (Mg ²⁺ ), aluminum (Al ³⁺ ) Electrochemical cell. The method of claim 1, wherein the dipole has the formula A _y X _z, or having the general formula A _y X _z-1 ^-q, wherein, A is Li, Na, K, Mg, and / or Al, X is S And / or O, 0 < _{z # 3} , y is sufficient to ensure the charge neutral of the dipole of the general formula A _y X _z , or ^-q of the dipole of the general formula A _y-1 X _z ^-q And 1 &lt; / = q &lt; / = 3. The electrochemical cell of claim 1, wherein the dipole comprises 50% by weight or less of the dipole additive. 9. The composition of claim 8, wherein the dipole additive comprises one of the compounds having the general formula A _y X _z or a compound having the general formula A _y-1 X _z ^-q , or a combination thereof wherein A is Li, Na, K , Mg, and / or Al, and, X is S, O, Si, and / or OH, 0 <z≤3 and, y is the dipole charge neutrality of additives of the formula a _y X _z, or the formula a _{y z} ^-q _-1 X of sufficient to ensure -q charge of the dipole and additives, 1≤q≤3 the electrochemical cell. The electrochemical cell of claim 1, wherein the electrochemical cell has a cyclic lifetime of at least a thousand cycles. The electrochemical cell of claim 1, wherein the electrochemical cell exhibits a discharge current even when it does not receive energy from an external source at the time of its shutdown. The electrochemical cell of claim 1, wherein the electrochemical cell exhibits a self-circulating component of charge or discharge current and / or voltage at a fixed control current imposed by an external potentiostat. The electrochemical cell of claim 1, wherein the electrochemical cell is reversibly and dendritically plated with working ions on the anode during charging. The electrochemical cell of claim 1, wherein the electrochemical cell exhibits self-charging without controlled charge current. The electrochemical cell of claim 1, wherein the electrochemical cell exhibits a self-charging current component having a controlled charge current component. The electrochemical cell of claim 1, wherein the electrochemical cell exhibits a self-charging component without controlled discharge current. The electrochemical cell of claim 1, wherein the electrochemical cell exhibits self-charging without controlled discharge current. The electrochemical cell of claim 1, wherein the electrochemical cell has a charge / discharge Coulomb efficiency of greater than 100%. The electrochemical cell of claim 1 wherein the cell exhibits a measured charge or discharge current that is less than the control current. The electrochemical cell of claim 1, wherein the electrochemical cell has a charge current greater than the control current upon charging. The electrochemical cell of claim 1, wherein the electrochemical cell has a current measured in the opposite direction of the control current. The electrochemical cell of claim 1, wherein the electrochemical cell has a measured discharge current greater than the control current at the time of discharge and exhibits self-circulation of both the measured discharge current and voltage. The electrochemical cell of claim 1, wherein the electrochemical cell exhibits an alternating current having a duration of at least one minute. The electrochemical cell of claim 1, wherein the electrochemical cell exhibits an alternating current having a duration of at least one day.

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