WO2020214829A1

WO2020214829A1 - Magnetic particle flow battery

Info

Publication number: WO2020214829A1
Application number: PCT/US2020/028545
Authority: WO
Inventors: William Charles NUNNALLY; Kelly Scott JACOBSEN; David Michael Johns; Bret Alan RAYMIS; Brenton Edgar BENNETT
Original assignee: Pwrjoule Llc
Priority date: 2019-04-16
Filing date: 2020-04-16
Publication date: 2020-10-22

Abstract

A system and method including an electrochemical battery system comprising an ion transfer cell container including a first electrode flow channel, a second electrode flow channel, and an ion-permeable membrane separating the first and second electrode flow channels. A first electrode in the first electrode flow channel and a second electrode in the second electrode are configured to be coupled to an electrical load or to an electrical power source. A first liquid electrolyte slurry comprising a first type of first particles that are configured to accept or deploy at least one electron-ion pair and are configured to be magnetically susceptible. The first liquid electrolyte slurry is configured to flow through the first electrode flow channel in one of two opposite directions around the first electrode. The first particles are configured to contact the first electrode based at least in part on a generated magnetic field. The generated magnetic field is generated based at least in part on a current flowing through the first and second electrodes.

Description

Description/Specification

Title: Magnetic Particle Flow Battery

A. Background

[HI] The invention relates generally to energy storage systems and more particularly to

particle flow batteries.

B. Brief Description of the Drawings

[H2] Other objects and advantages of the invention may become apparent upon reading the detailed description and upon reference to the accompanying drawings.

[H3] Figure 1 is a perspective view of a LI Battery Active Volume, in accordance with some embodiments.

[H4] Figure 2 is a perspective view of a battery flow ion transfer cell, in accordance with some embodiments.

[H5] Figure B is a block diagram showing the operation of an MPFB ion transfer cell, in

accordance with some embodiments.

[H6] Figure 4 is a cross-sectional view of the construction of one type of lithium ion magnetic particles, in accordance with some embodiments.

[H7] Figure 5 is a cross-sectional view of the construction of matrix particles, in accordance with some embodiments.

[H8] Figure 6 is a block diagram showing current flow in an ion transfer cell, in accordance with some embodiments.

[H9] Figure 7 is a block diagram showing a fundamental base ion transfer cell, in accordance with some embodiments. l [H10] Figure 8 is a block diagram showing four base ion transfer cells connected in series, in accordance with some embodiments.

[Ull] Figure 9 is a block diagram showing a system of ITCs with an inter-cell magnetic coil connection, in accordance with some embodiments.

[1112] Figure 10 is block diagram showing the magnetic particle flow battery, in accordance with some embodiments.

[1113] While the invention is subject to various modifications and alternative forms, specific embodiments thereof are shown by way of example in the drawings and the

accompanying detailed description. It should be understood, however, that the drawings and detailed description are not intended to limit the invention to the particular embodiments. This disclosure is instead intended to cover all modifications, equivalents, and alternatives falling within the scope of the present invention as defined by the appended claims.

C. Detailed Description

[H14] Figure 1 is a perspective view of a LI Battery Active Volume, in accordance with some embodiments.

[H15] Lithium Ion batteries (LIBs) are one of the dominant energy storage technologies. Lithium Ion batteries store energy by transferring Lithium ions from one side of an

electrochemical cell to the other side of the electrochemical cell. The stored energy is recovered by transferring the Lithium ions across the electrochemical cell in the reverse direction. In typical LIBs, the lithium ions are inserted or inculcated within the electrode material structure on each side of the electrochemical cell.

[H16] In typical LIBs and batteries in general, the energy conversion function and the energy storage function are embodied in the same volume. Thus, it may be more difficult to maximize the energy storage density and the energy conversion or power density at the same time. [H17] In addition, in typical LIBs, only a small fraction of the overall volume in a battery is active at any point during charge and discharge as illustrated in Figure 1. The remaining volume consists of energy stored volume, energy depleted volume, and the ion conductive and electron conducting media separating the positive and negative regions of the structure, also illustrated in Figure 1.

[H18] For example, in a typical LIB, the active regions, where ions are deployed from or

inculcated into the battery materials with a corresponding electron being recovered, have an effective thickness of only microns and the ions move at only microns/second. If, for example, a charging current of 1 amp flows through a one square cm of the LIB cross section with a LiFePC>4 cathode and a Graphite anode, the resulting active material layer thickness and the effective velocity of that layer are shown in Table 1.

Table 1 Lithium Ion Battery Active Layer Example

[H19] Table 1 calculates the thickness of the active layer employed in producing a current

density of 1 A/cm² for LiFeP04 cathode material of 10 microns and the velocity of the moving active layer of only 10 microns/s. Table 1 also calculates the thickness of the active layer employed in producing a current density of 1 A/cm² for Graphite anode material of only 3.3 microns and a velocity of 3.3 microns/s. The table illustrates the small volume of material that is active during charge or discharge of a typical Lithium Ion battery. In typical Lithium Ion batteries, the maximum current density is much less than 0.1 A/cm². Thus, typical Lithium Ion batteries may produce ampere currents by fabricating a large cross sectional area of materials between the anode and cathode conductors, for example.

[H20] In some embodiments, the typical battery volume illustration 100 of Figure 1 illustrates the ion transfer process in a typical battery. The illustration may not be an accurate electrochemical portrayal. The illustration consists of an anode (101) and cathode (102), with anode materials (103) and cathode materials (108) separated by an ion-permeable separator layer (113). In a battery charging (store) operation, bound ions are released from the cathode materials and transferred to the anode materials to be bound. The anode materials layer (103) consist of ion bound region (104), an ion free region, and a very thin active (105) region where the ions from the cathode region are chemically bound. The cathode materials layer (108) consist of an ion bound region (112), an ion free region (110), and a very thin active region (111) where ions are being chemically released. Also illustrated in Figure 1 is the diffusion of electrons (114) and (115) in the bound ion regions. Similarly, in the free ion regions, ions are diffusing (116), moving from the cathode active region (111) to the anode active region (105). Both the ion diffusion (116) and the electron diffusion (114) and (115) produce thermal energy in the battery during the charge (store) and the discharge (recover) processes. Figure 1 illustrates the relationship between the charging current (117) and the effective thickness of the active layers. In some embodiments, the current densities in batteries is limited to a small fraction of an ampere per square cm of cross section. For the purposes of this illustration, a one ampere current (117) per square cm is assumed, and the resulting thickness of the active layer and the velocity of the layer are shown in Table 1. In some embodiments, active layer thicknesses of only several microns are required to provide the assumed current, and these layers move at very slow velocities. Thus, in some embodiments, (1) at any point of time, the majority of the battery volume is not involved, and (2) the part of the battery volume that is not active serves to generate thermal energy due to the diffusion of electrons and free ions through the materials. [H21] In some embodiments, typical Lithium Ion batteries generally use very thin layers of material in the electrochemical cell that typically operate at the range of milli ampere per square cm. Desired output current may be obtained, in some embodiments, by increasing the electrode area in order to optimize the battery efficiency, either for energy density or power density. However, in some embodiments, LIBs may be limited by the inefficient use of volume that limits the cost and volume/weight effectiveness of storing large quantities of energy from which high-power density is required.

[H22] In some embodiments, in typical LIBs and batteries in general in large energy storage applications, there may be danger resulting from a fault, shorting the battery electrodes causing the entire energy stored to be deposited in the fault with potentially explosive results. In addition, in typical LIBs, thermal energy generated during high current density charge or discharge may, in some embodiments, result in battery failure potentially resulting in fire or electrode shorting.

[H23] Figure 2 is a perspective view of a battery flow ion transfer cell, in accordance with some embodiments.

[H24] Figure 2 illustrates an example of a battery where the energy storage volume is separated from the energy conversion volume. In some embodiments, separating the energy storage volume from the energy conversion volume results in a flow battery or fuel cell.

In a flow battery or fuel cell, most of the energy storage is in the form of an anode slurry and a cathode slurry, which may be stored in separate tanks. The anode and cathode slurries may be pumped through an Ion transfer cell (ITC), illustrated in Figure 2, separated by a separator layer. In the ITC, the ion-electron exchange layers for both the anode and cathode are at the surface of the electrodes which reduces internal heating due to ion and electron diffusion through inactive materials.

[H25] The flow battery configuration physically separates the energy storage volume and the active electrochemical volume. In some embodiments, the active electro-chemical materials may be formed of magnetic particles in electrolyte slurries. A positive or cathode slurry and a negative or anode slurry may be formed and may be stored in tanks separated from the active electrochemical processes.

[H26] In some embodiments, the electrochemical processes may be performed in an Ion

Transfer Cell connected to the slurry tanks via pumps and tubes. The anode and cathode slurries may be pumped through the Ion Transfer Cell where ions in one electrode slurry magnetic particle are transferred across the cell through a separator to the magnetic particles in the other electrode slurry. The ion transfer occurs during charge (store) process in one direction and in the opposite direction during the discharge (recover) process.

[H27] In some embodiments, the electrodes may employ the transfer cell current to produce a magnetic field to facilitate better contact between the magnetic particles flowing through the Ion Transfer Cell and their respective electrodes during the magnetic particles' cell transit. In some embodiments, better electrode contact between the magnetic particles and the electrodes during Ion Transfer Cell transit facilitates an increased probability that the magnetic particles deploy/accept an ion while simultaneously deploying/accepting an electron to remain charge neutral.

[H28] In some embodiments, the manufacturing materials required for a magnetic particle flow (MPFB) may cost less thus reducing the overall cost of the MPFB. The manufacturing materials, in some embodiments, may also weigh less and take less volume thus reducing the weight and cost of the battery as well.

[H29] In some embodiments, separating the active materials from the Ion Transfer Cell may increase safety as only the quantity of active materials necessary to produce the required output power is present in the ITC. Thus, the potential for electrical failures may be reduced. In addition, in some embodiments, the electrical safety and long-term storage of energy may be improved as the two types of magnetic particles are physically separated from each other, and both types of magnetic particles remain charge neutral before and after transiting the Ion Transfer Cell. [H30] In some embodiments, the MPFB is configured to store electrical energy in a flow battery configuration based on electrolyte slurries of magnetically susceptible particles. The MPFB may also be configured to separate the portion of the battery volume that is inactive from the very small portion of the battery volume involved in electrochemical activity at any point in time. The MPFB may also be configured to replace the energy storage materials normally attached to electrodes in a typical electro chemical cell or battery with slurries of inherent or fabricated magnetically susceptible particles of energy storage materials. The MPFB may also be configured to fashion the electro chemical cell electrodes in a manner that employs the electro chemical cell current, both during store (charge) or recover (discharge) functions, to produce a magnetic field for the purpose of attracting magnetically susceptible slurry particles to insure magnetically susceptible particles have a higher probability to exchange electrons and ions at the cell electrodes.

[H31] Figure 2 illustrates a very basic flow battery or fuel cell configuration 200 in which the inactive anode and cathode materials have been removed. In some embodiments, the flow battery illustration of Figure 2 consists of an anode electrode (201), an anode active material layer (206), a flow (205) of additional anode material (204), an ion permeable separator membrane (203), a flow (208) of additional cathode material (207), a cathode active material layer (209), and a cathode electrode (202). In this illustration, the active cathode layer (209) and the active anode layer (206) occur at the corresponding electrodes reducing the distance ions and electrons must diffuse and allowing cooling of the flowing materials.

[H32] In some embodiments, the additional anode materials (204) and additional cathode materials (207) are slurries composed of corresponding micro particles in liquid electrolytes. In this manner, the energy stored in the system may be determined at least partially by the size of the slurry tanks and the power level may be determined at least partially by the size of the flow cell plates.

[H33] Figure 3 is a block diagram showing the operation of an MPFB ion transfer cell, in

accordance with some embodiments. [H34] In some embodiments, the components of the ion transfer operation during the charge process of a Magnetic Particle Flow Battery (MPFB) Ion Transfer Cell system BOO is illustrated Figure 3. Not shown in Figure 3 are four external tanks holding the two types of slurries before and after transiting the ITC and the associated bidirectional pumps for moving the slurries. The particle/slurry flow as shown in Figure 3 is for the charge (store) operation. The flow would be reversed for the discharge (recover) operation. In some embodiments, the magnetic particles may be pumped with a magnetic traveling wave pump in either direction.

[H35] The components illustrated in Figure 3 include the Ion Transfer Cell, the "P" slurry with cathode micro particles and the Positive electrode, and the "N" slurry with anode micro particles and the negative electrode. The charge (store)/discharge(recover) controls facilitate at least partially the charge flow into the MPFB from the charging source and out of the MPFB to the load.

[H36] In some embodiments, Figure 3 illustrates the process by which energy is

stored/recovered as micro particles (306) and (307) flow through Ion Transfer Cell (301). The Ion Transfer Cell (ITC) consists, in some embodiments, of a positive or cathode electrode (302), a negative or anode electrode (303), a cathode flow channel (304), an anode flow channel (305), and an ion-permeable separator membrane (318). In some embodiments, the ion-permeable separator membrane (318) allows ions to move from anode flow channel (305) to/from cathode flow channel (304) and from cathode flow channel (304) from/to anode flow channel (305) depending upon whether the ITC is in charge or discharge mode. It should be noted that, in some embodiments, the ITC may operate with only one type particles if, for example, the other side of the ITC is fixed with ions being plated or dissolved.

[H37] Figure 3 also illustrates the charge source (314), the load (315), and the power control system (316). The power control system (316), in some embodiments, is configured to either direct the energy from the charging source (314) to the Ion Transfer Cell (301) or from the Ion Transfer Cell (301) to the Load (315). [H38] In addition, in some embodiments, the power control system is configured to convert the current (317) flowing to or from the Ion Transfer Cell (301) to a series of pulses rather than being continuous. In some embodiments, a pulsed current may facilitate the magnetic particles' flow through the ITC. In some embodiments, a pulsed current may be used to facilitate better flow of the particles through the ITC by turning the magnetic field generated by the current one and off, as will be discussed further below.

[H39] In some embodiments, the cathode micro particles (306) are magnetically susceptible, either inherently or fabricated so, and are placed in an electrolyte slurry. In some embodiments, the cathode micro particles (306) are charge neutral by containing an equal number of transfer ions (308) and electrons (309). Similarly, the anode particles (307) are magnetically susceptible, either inherently or fabricated so, and are placed in an electrolyte slurry. In some embodiments, the anode particles (307) are also charge neutral.

[H40] In some embodiments, depending on whether the ITC is in the charge or store process, the cathode slurry particles enter/exit (310) from/to the cathode(+) tank (not shown) through the cathode flow channel (304) in the Ion Transfer Cell (301) exiting/entering (311) to/from the cathode(-) tank (not shown). The anode slurry particles similarly enter/exit (312) from/to the anode(-) tank (not shown) through the anode flow channel (305) in the Ion Transfer Cell (301) and exit/enter (313) to/from the anode(+) tank (not shown). It should be noted that the flow directions for the anode slurry and the cathode slurry may be in the same direction, in opposite directions, in orthogonal directions, or flow in other configurations while interacting in the ITC.

[H41] In some embodiments, in the store process, the cathode micro particles contact (319) the positive electrode (302) in order to deploy an electron (309) while simultaneously deploying an ion (308) to remain charge neutral. The electric field between the positive electrode (301) and the negative electrode (303) moves the ion through the separator (318) to be inserted or inculcated into an anode micro particle (307). In some

embodiments, for an anode micro particle (307) to accept an ion (308), the anode particle contacts (320) the negative electrode (303) to simultaneously accept an electron to remain charge neutral. The ion/electron transfer process occurs in an opposite sequence when the flow battery is operated in the discharge or recover mode.

[H42] Figure 4 is a cross-sectional view of the construction of one type of lithium ion magnetic particles, in accordance with some embodiments.

[H43] In some embodiments, two types of magnetically susceptible particles are defined by this invention: 1) fabricated magnetically susceptible particles and 2) inherently magnetically susceptible particles. Particles associated with both the cathode or positive "P" terminal and particles associated with the anode or negative "N" terminal are to be deployed in "P" and "N" liquid electrolyte slurries respectively. In some embodiments, the dimensions of the particles would be sub-micron in diameter to facilitate suspension in the electrolyte. However, fabricated micro particles with larger diameters may also be employed.

[H44] An example of fabricated magnetically susceptible micro particles for a typical Lithium Ion battery are illustrated in Figure 4. A magnetically susceptible core, such as iron oxide, is surrounded with "P" material such as LiFeP04 for the "P" particles or "N" material such as Graphite for the "N" particles. The shell thickness of the magnetic particles may be designed to allow ion diffusion during the ITC transit. In some embodiments, the particle binder material may be ion permeable.

[H45] Two types of fabricated, magnetically susceptible particles are shown as examples in

Figure 4: a cathode micro-particle (401) and an anode micro particle (402). Both types of particles may be employed in a magnetic particle flow battery or fuel cell. It should be noted only one type of particle may be used when the opposite electrode is fixed.

[H46] In some embodiments, the core-shell magnetically susceptible particles shown are

constructed with a magnetically susceptible core (403) or a material such as iron oxide or other material with a large magnetic susceptibility. The core may be surrounded in the cathode particles (401) with a material (404) that may be used as an ion source, such as LiFeP04, for example, in a Lithium Ion battery. The anode micro particle may be surrounded with a material (405) that may be used as an ion sink, such as Graphite, for example, in a Lithium Ion battery implementation. It should be noted that various other core materials (403) and shell materials (404) and (405) may be employed in a Magnetic Particle Flow Battery or fuel cell depending on the implementation.

[H47] Figure 5 is a cross-sectional view of the construction of matrix particles, in accordance with some embodiments.

[H48] Figure 5 shows an alternate particle construction where the magnetically susceptible material is distributed throughout the magnetic particle active material volume to form a matrix particle.

[H49] In some embodiments, the second type of particles may be sub-micron diameter particles of electro chemical materials that are inherently magnetic, such as iron oxides or manganese compounds. A few such materials are listed in Table 2, including Iron Oxide, as a reference.

Table 2 Examples of Inherently Magnetically Susceptible Battery Materials [H50] In some embodiments, the inherently magnetically susceptible (IHM) particles in Lithium

Ion batteries may be loaded or inculcated with Lithium ions. For example, Manganese Oxide becomes Li3Mn204 which is a cathode material that serves as a source of Lithium ions. Another example is Iron Oxide which can be inculcated with Lithium ions to form Li₅(FeO)₄. [H51] In some embodiments, the matrix magnetically susceptible particles, shown in Figure 5, may be constructed with magnetically susceptible material (503) or material such as Iron oxide or other material with a large susceptibility distributed throughout the particle. The matrix cathode particle (501) may be formed with a material (505) that is an ion source, such as LiFeP0₄ for a Lithium Ion battery implementation. In some embodiments, the matrix anode micro particle (502) may be formed with a material (504) that is an ion sink, such as Graphite for a Lithium Ion battery implementation. Various other core materials (503) and various other major anode and cathode materials (504) and (505) may be employed in a Magnetic Particle Flow Battery or fuel cell, again depending on the specific implementation.

[H52] Figure 6 is a block diagram showing current flow in an ion transfer cell, in accordance with some embodiments.

[H53] In some embodiments, a magnetic particle either accepts or expels an ion while expelling or accepting an electron to remain charge neutral while moving through the ITC. In some embodiments, particle-electrode contact during ITC transit may be enhanced by configuring the electrodes to produce an attractive magnetic force on the particles using the ITC current, for example. In some embodiments, a pulsed current may be necessary to facilitate better flow of the magnetically susceptible particles through the ITC as the slurry viscosity may rise (by several to ten orders of magnitude, in some embodiments) in the presence of a current-generated magnetic field. In some embodiments, the charge/discharge control system may modulate/pulse the input and output currents. As such, the particles may alternate between being attracted to the electrodes when the current is present and being free to flow through the ITC when the current is not present. It should be noted that, in certain configurations, the magnetic particle slurries may behave similarly to a ferro fluid in terms of its viscosity increase in the presence of a magnetic field.

[H54] It should be noted that the magnetic particles (being magnetically susceptible) are

configured to move toward higher magnetic field energy density. In some embodiments, the ITC electrodes are designed to produce the maximum magnetic field at the surface of the electrodes. The magnetic field outside the surface of a rod or wire is proportional to the inverse of the distance from the center of the rod or wire (along its radius). As such, the maximum magnetic field and magnetic energy density is at the surface of the wire or rod. The magnetic field strength, B(r), for a cylindrical rod or wire is proportional to l/r, where / is the current flowing through the wire and r is the distance from the center of the wire.

[H55] In such embodiments, the maximum magnetic field intensity occurs at the surface of the electrode, which is also the location of the electro chemical potential drop. In some embodiments, the electrodes may be constructed of wires or rods with a small radius to maximize the magnetic field at the surface of the electrodes.

[H56] Figure 6 illustrates the electron current flow from the cathode input terminal through the cathode, distributed ion current flow through the cathode slurry, the separator, the anode slurry to the anode, and then the electron flow through the anode electrode to the anode terminal. Figure 6 also identifies the electro chemical potential due to the slurry potentials and the distributed ionic resistance of the flow cell. In some embodiments, the ionic resistance is a function of the anode-cathode spacing, the cell length, and the electrolyte-slurry conductivity. In some embodiments, the length of the flow cell may be determined by the ionic resistance which is designed to generate a small fraction of the cell voltage.

[H57] In the Ion Transfer Cell (601) of Figure 6, operating in the charge or store mode consists of a cathode (602) surrounded by a cathode particle slurry flow channel (611), an anode wire electrode (603) surrounded by an anode particle slurry flow channel (612), with the flow channels separated by an ion permeable membrane (604). In some embodiments, the cathode electrode (602) may be fabricated with a small diameter wire that produces a magnetic field (613) around the wire. Similarly, the anode electrode (603) may be fabricated with a small diameter wire that produces a magnetic field (614) around the wire. [H58] In some embodiments, the magnetic fields (613) and (614) may be generated by the current flowing through the ITC. The current flowing through the ITC flows as cell current (607) entering the cathode terminal (605), flowing as ions through the cathode slurry (611), through the separator (604), the anode slurry (612), to the anode electrode (603), and exiting through the anode terminal (606).

[H59] In some embodiments, the cathode magnetic field (613) attracts cathode magnetic

particles in the cathode slurry (611) to facilitate contact between the magnetic particles and the cathode (602) to facilitate the release of both an electron and an ion. The ions flow through the cathode slurry (611) and the anode slurry (612)— represented by the ionic resistance (610) and the electro chemical potential (609) determined by the cathode and anode materials. The electron flows toward the cathode input terminal (605).

[H60] In some embodiments, the anode magnetic field (614) attracts anode magnetic particles in the anode slurry (612) to the anode (603) to facilitate contact between the magnetic particles and the electrode to facilitate the acceptance of an electron and an ion by the magnetic particles. The electrons flow from the anode terminal (606) to the anode particle partially due to the anode electrode (603) contact with the anode particle.

[H61] It should be noted that the cathode terminal (605) and the anode terminal (606) may be placed at opposite ends of the cell to facilitate the cell current (607) flowing through the entire cell. The cathode terminal (605) and the anode terminal (606) locations with respect to the cell (601) may be interchanged as may be seen in the series cell connection in Figure 7, for example.

[H62] Figure 7 is a block diagram showing a fundamental base ion transfer cell, in accordance with some embodiments.

[H63] An example of a fundamental or base size ITC cell is shown in Figure 7.

[H64] In some embodiments, the electrode current flow may be designed such that the current flows along the cylindrical electrodes in such a manner as to ensure that the magnetic field is produced along the entire length of the electrodes. The cell current between the anode and cathode may be distributed along the electrodes, such that the maximum magnetic field occurs at the surface of the electrodes.

[H65] As the energy density of Lithium Ion materials is large, in some embodiments, thin layers of slurries may provide relatively large currents. The flow cross section and velocity of both the cathode slurry and the anode slurry in the ITC may be determined by the current that the rod/wire can support as shown in Table 3 below.

Table 3 Slurry Composition, Flow Rate and Maximum Cell current

[H66] Table 3 demonstrates the large energy density of typical Lithium Ion battery materials in both the anode and cathode slurries as seen by the large electrolyte fraction in the anode and cathode slurries that is employed to produce a current of 11 Amperes. The electrolyte fraction may be increased to limit the current collected from exceeding the fusing current limit of the small diameter wire electrodes. It should be noted that the small diameter wires are employed as electrodes to provide the largest magnetic field intensity at the wire surface. Table 3 also demonstrates the design of the slurries for equal anode and cathode charge densities by adjusting the electrolyte fraction in each slurry which enables equal anode and cathode flow velocities. An alternate approach is to adjust the flow velocities of the anode and cathode slurries separately with a typical electrolyte fraction. Finally, Table 3 demonstrates that very small velocities of slurry flow are capable of producing significant currents in a very small dimension cell.

[H67] In some embodiments, the base cell output current may be equal to the charge injection rate in the slurry flow, for each electrode. It should also be noted that the charge injection rate for the anode and cathode slurries may be made equal by adjusting the electrolyte fraction and the quantity of the active materials. Furthermore, in some embodiments, the maximum output current of the base ITC may be limited by the maximum current the wire can support.

[H68] In some embodiments, the charge injection rate into the flow area surrounding the wire may be dependent upon the flow velocity and the charge density of the slurry. The charge injection rate for the anode and the cathode flow area may be matched by adjusting the slurry electrolyte fraction. Other options, however, may also be used. The cathode flow and the anode flow can be in the same direction, in countering directions, or in other configurations.

[H69] In some embodiments, a small flow velocity may produce significant currents due to the high charge density of the slurry materials. In some embodiments and implementations, the wire diameter may be 0.020 inches or about 24 gauge with a maximum current when insulated of about 5 amps and up to 12 amps when cooled.

[H70] In some embodiments, the fundamental base Ion Transfer Cell (701), shown in Figure 7, may be deployed in parallel and/or series combinations to deliver the desired system voltage and current combination. In some embodiments, two types of base ITC cells may be deployed: (1) a finite energy store cell in which only one side employs magnetic particles while the other side is a fixed electrode, and (2) an infinite energy storage cell in which both sides of the cell employ magnetic particles.

[H71] Shown in Figure 7 is an example of an infinite energy store base cell (701). In some

embodiments, base cell (701) consists of a cathode wire electrode (70S) surrounded by a cathode magnetic particle slurry flow channel (702) and an anode wire electrode (706) that is surrounded by an anode magnetic particle slurry flow channel (707). The cathode slurry flow channel (702) is separated from the anode slurry flow channel (707) by an ion permeable membrane (708). In some embodiments, the base cell shown in Figure 7 may be the physical embodiment of the Ion Transfer Cell operation diagram shown in Figure 3, in which the electrodes are replaced by small diameter wires for the purpose of maximizing the magnetic field at the electrode surface.

[H72] In some embodiments, in the charge or store operational mode, the base ITC of Figure 7, cathode magnetic particle slurry is moved (704) from the cathode(+) slurry tank (not shown) through the cathode slurry flow channel (702) along the cathode wire electrode (703). After deploying the transfer ions, the cathode magnetic particle slurry is moved (711) to the cathode(-) tank (not shown). Simultaneously, anode magnetic particle slurry is moved (705) from the anode(-) slurry tank (not shown) through the anode slurry flow channel (707) along the anode wire electrode (706). After accepting the transfer ions, the anode magnetic particle slurry is moved (712) to the cathode(-) tank (not shown). In the charge or store process, the cell current enters the cathode terminal (710) flows through ion current from the cathode (703) to the anode (706) and exits the anode terminal (709).

[H73] Figure 8 is a block diagram showing four base ion transfer cells connected in series, in accordance with some embodiments.

[H74] In some embodiments, many base cells may be connected in series to increase the system output voltage as shown in Figure 8. In Figure 8, the input connection changes from input to output in adjacent cells to ensure that the cell current produces maximum uniform magnetic field in all cells. [H75] In some embodiments, the flow length of the base ITC cell may be determined in a tradeoff between the ionic impedance of the cell, which may at least partially be a function of the geometry, the electrolyte conductivity, and the flow power requirements. In some embodiments, the ionic resistance may be designed to be very small, allowing the battery output voltage to be large.

[H76] In some embodiments, the flow battery or fuel cell is designed to parallel several series strings of the base Ion Transfer Cell. Each base ITC cell may have the potential to produce a maximum current of 10-12 amps and a voltage determined by the electrochemical makeup of the slurries. In embodiments where LiFeP04 and Graphite are used, the open circuit voltage per ITC base cell would be approximately 3.2 volts.

[H77] In some embodiments, to increase the system voltage, a number of base ITC cells (801) may be connected in series as shown in Figure 8. The successive stages may be connected such that the cathode terminal (802) is at the end of the cathode (807) and the anode terminal (803) is at the opposite end of the cell (801) at the end of the anode (808). The locations of the anode terminals (802) and (803) may be reversed in the next in-series ITC. Any number of ITC cells (801) may be connected in series using the cell interconnections (803), (804) and (805) as illustrated. The series cell connections in Figure 8 are (802) and (806).

[H78] Figure 9 is a block diagram showing a system of ITCs with an inter-cell magnetic coil

connection, in accordance with some embodiments.

[H79] An alternative of a ITCs is shown in Figure 9 connected in series. The series connection of Ion transfer cell (901) the cathode (902) and the anode (903) cross section may be modified in comparison to the ITC shown in Figure 8. In some embodiments, between each Ion transfer cell (901), a magnetic field coil (904) may be connected in series with the adjacent cells. The magnetic field coil (904) may be configured to employ the cell current to produce an additional magnetic field (909) that enhances the electrode magnetic field. The enhanced magnetic field may further facilitate the attraction of the magnetic particles to the anode (903) and cathode (902) for better contact of the magnetic particles to the electrodes. Also shown in the figure are the intercell connections (906), the input connection (907) to the series connections of cells channels, the cell current through the magnetic field coils (904) before entering the top ion transfer cell (901), and the cell current exits through another magnetic field coil and the series output connection (908).

[H80] Figure 10 is block diagram showing the magnetic particle flow battery, in accordance with some embodiments.

[H81] In some embodiments, the input charge or store current as well as the output discharge or recover current may be controlled using semiconductor switching power supply technologies. The ion transfer cell currents may be pulsed to allow the magnetic slurries to move during the low (or no) current periods of the cycle at least partially due to the increase in slurry viscosity during high current periods of the cycle.

[H82] Figure 10 shows an embodiment of the Magnetic Particle Flow Battery or Fuel Cell

system. In some embodiments, the input power may be converted to pulses by the bi directional Pulse Control system. The bi-directional pulse control system may also generate output in the form of pulses, again to allow the slurries to better flow during the low current/low magnetic field periods. Such a feature may allow the system to operate at higher slurry flow efficiency during both the charge or store and discharge or recover cycles.

[H83] In some embodiments, the MPFB system components are designed to support the series and/or parallel connections of base ITC cells (1001). The energy to be stored is provided by the input power terminals (1002) that feed a bi-directional power control system (1004). The power control system (1004) is configured to convert the incoming energy into current pulses. The power control system may also be configured to convert the output energy into current pulses.

[H84] In some embodiments, the cathode magnetically susceptible particles with ions in the electrolyte slurry may be stored in the cathode(+) tank (1004) while the anode magnetically susceptible particles without ions in the electrolyte slurry may be stored in the anode(-) tank (1010). The sign in the parenthesis represents the presence of transfer ions.

[H85] In some embodiments, the cathode magnetically susceptible particles without ions in the electrolyte slurry may be stored in the cathode(-) tank (1009), while the anode magnetically susceptible particles with ions in the electrolyte slurry may be stored in the anode(+) tank (1015). Again, the sign in the parenthesis represents the presence of transfer ions.

[H86] In some embodiments, in the charge or store mode, the ion rich cathode slurry is pumped (1005) to the cathode(+) manifold (1006) and into the series and/or parallel combination of base ITC cells (1001). Simultaneously, the ion deficient anode slurry is pumped (1011) to the anode(-) manifold (1012) and into the series-parallel of base ITC cell assembly (1001).

[H87] In some embodiments, in the charge or storage mode, as the anode and cathode slurries move through the ITC base cell assembly (1001), the ions are released from the cathode particles and transferred to the anode particles, partially due to the influence of the cell current magnetic fields. During the anode and cathode flow, the power control system injects current pulsed in the ITC cell assembly (1001), which motivates the transfer of ions from the cathode particles to the anode particles.

[H88] In some embodiments, in the charge mode, the cathode particles, now without ions, exit the ITC assembly through the cathode(-) manifold (1007) and are pumped into the cathode(-) tank (1009). The anode slurry particles, now with ions, exit the ITC assembly through the anode(+) manifold (1013) and are pumped into the anode(+) tank (1015).

[H89] In some embodiments, the quantity of energy stored may be dependent upon the

quantity of cathode and anode slurries that are pumped through the system. The energy may be stored in the charge neutral micro particles in the anode(+) tank. The stored energy can be recovered by utilizing the particles in the cathode(-) tank and reversing the anode and cathode flow direction through the ITC assembly. In the discharge or recover mode, the power control system (1004) is configured to deliver the output current in the form of pulses to the output terminals (1002).

[H90] It is understood that the implementation of other variations and modifications of the present invention in its various aspects will be apparent to those of ordinary skill in the art and that the invention is not limited by the specific embodiments described. It is therefore contemplated to cover by the present invention any and all modifications, variations or equivalents that fall within the spirit and scope of the basic underlying principles disclosed and claimed herein.

[H91] One or more embodiments of the invention are described above. It should be noted that these and any other embodiments are exemplary and are intended to be illustrative of the invention rather than limiting. While the invention is widely applicable to various types of systems, a skilled person will recognize that it is impossible to include all of the possible embodiments and contexts of the invention in this disclosure. Upon reading this disclosure, many alternative embodiments of the present invention will be apparent to persons of ordinary skill in the art.

[H92] The previous description of the disclosed embodiments is provided to enable any person skilled in the art to make or use the present invention. Various modifications to these embodiments will be readily apparent to those skilled in the art, and the generic principles defined herein may be applied to other embodiments without departing from the spirit or scope of the invention. Thus, the present invention is not intended to be limited to the embodiments shown herein but is to be accorded the widest scope consistent with the principles and novel features disclosed herein.

[H93] The benefits and advantages that may be provided by the present invention have been described above with regard to specific embodiments. These benefits and advantages, and any elements or limitations that may cause them to occur or to become more pronounced are not to be construed as critical, required, or essential features of any or all of the claims. As used herein, the terms "comprises," "comprising," or any other variations thereof, are intended to be interpreted as non-exclusively including the elements or limitations that follow those terms. Accordingly, a system, method, or other embodiment that comprises a set of elements is not limited to only those elements and may include other elements not expressly listed or inherent to the claimed embodiment.

[H94] While the present invention has been described with reference to particular

embodiments, it should be understood that the embodiments are illustrative and that the scope of the invention is not limited to these embodiments. Many variations,

modifications, additions and improvements to the embodiments described above are possible. It is contemplated that these variations, modifications, additions and improvements fall within the scope of the invention as detailed within the following claims.

Claims

1. An electrochemical battery system comprising: an ion transfer cell container comprising a first electrode flow channel, a second electrode flow channel, and an ion-permeable membrane separating the first and second electrode flow channels; a first electrode in the first electrode flow channel and a second electrode in the second electrode, wherein the first and second electrodes are configured to be coupled to an electrical load or to an electrical power source based at least in part on whether energy is being stored or recovered from the system; a first liquid electrolyte slurry comprising a first type of first particles, wherein the first particles are configured to accept or deploy at least one electron-ion pair, based at least in part on whether energy is being stored or recovered from the system, wherein the first particles are configured to be magnetically susceptible; wherein the first liquid electrolyte slurry is configured to flow through the first electrode flow channel in one of two opposite directions around the first electrode, based at least in part on whether energy is being stored or recovered from the system;

wherein the first particles are configured to contact the first electrode based at least in part on a generated magnetic field, wherein the generated magnetic field is generated based at least in part on a current flowing through the first and second electrodes.

2. The system of claim 1, comprising one or more coils placed in the vicinity of the first electrode, wherein the coils are configured to generate an additional magnetic field in the vicinity of the first electrode based at least upon the current flowing through the coils.

3. The system of claim 1, comprising a power controller configured to vary the current magnitude.

4. The system of claim 3, wherein the power controller is configured to pulse the current.

5. The system of claim 1, wherein one of the first electrode/flow channel and the second electrode/flow channel is an anode electrode/flow channel and the other one is a cathode electrode/flow channel.

6. The system of claim 1, comprising a bidirectional pump configured to pump the first liquid electrolyte slurry selectively in one of two opposite directions through the first electrode flow channel based at least in part on whether energy is being stored or recovered from the system, causing the first liquid electrolyte slurry to flow around the first electrode.

7. The system of claim 6, further comprising at least two tanks for storing the first liquid electrolyte slurry in each of the two directions.

8. A method comprising: flowing a first electrolyte slurry through a first electrode flow channel, wherein the first liquid electrolyte slurry comprises a first type of first particles, wherein the first particles are configured to accept or deploy at least one electron-ion pair, based at least in part on whether energy is being stored or recovered, wherein the first particles are configured to be magnetically susceptible,

wherein the first liquid electrolyte slurry is configured to flow through a first electrode flow channel comprising a first electrode in one of two opposite directions around the first electrode, based at least in part on whether energy is being stored or recovered,

wherein the first electrode in the first electrode flow channel and a corresponding second electrode in a second electrode flow channel are configured to be coupled to an electrical load or to an electrical power source based at least in part on whether energy is being stored or recovered; attracting the first particles to the first electrode based at least in part on generating a magnetic field based at least in part on a current flowing through the first and second electrodes.

wherein the first particles are configured to contact the first electrode based at least in part on a generated magnetic field, wherein the generated magnetic field is generated.

9. The method of claim 8, comprising generating an additional magnetic field in the vicinity of the first electrode based at least upon the current flowing through coils in the vicinity of the first electrode.

10. The method of claim 8, comprising varying the current magnitude using a power controller.

11. The method of claim 10, comprising pulsing the current magnitude using the power controller.

12. The method of claim 8, wherein the first electrode is either a cathode or an anode electrode and wherein the first electrode flow channel is either a cathode or an anode electrode flow channel.

13. The method of claim 8, comprising pumping the first liquid electrolyte slurry

selectively in one of two opposite directions through the first electrode flow channel based at least in part on whether energy is being stored or recovered, causing the first liquid electrolyte slurry to flow around the first electrode.