Patent Description:
Fossil energy resources will be exhausted inevitably, and renewable energy sources, such as solar energy and wind energy, have attracted more and more attention. However, the renewable energy resources are usually discontinuous, and a serious impact may be caused on the electricity grid due to the instability. Through the flow cell energy storage technology, it is able for the renewable energy resources to achieve peak-load shifting in a better manner.

A flow cell stack is a core component of a flow cell energy storage system, and the cost performance of the energy storage system depends on the performance of the flow cell stack.

Currently, in order to improve electric energy conversion efficiency, usually a length of an electrode through which an electrolyte flows needs to be reduced. However, an area of the electrode needs to be increased to provide same power, i.e., the length of the electrode needs to be increased. In the case of a longer electrode, there is a challenge for the sealing of a flow channel of the electrode. Currently, it is impossible for the flow cell to meet the requirement on actual power as well as the sealing of the flow channel. <CIT>, <CIT>, <CIT> and <CIT> disclose different configurations for flow batteries with arch-like flow channels.

An object of the present disclosure is to provide a flow battery and a cell stack, so as to improve the electric energy conversion efficiency.

In order to solve the above-mentioned problem, the present disclosure provides the following technical solutions.

In one aspect, the present disclosure provides in some embodiments a cell stack of a flow battery, including: a first end plate; a second end plate; and at least one cell module arranged between the first end plate and the second end plate. Each cell module includes a first flow channel end plate, a second flow channel end plate arranged opposite to the first flow channel end plate, and single-cell assemblies arranged between the first flow channel end plate and the second flow channel end plate. The single-cell assemblies include at least three hermetically-assembled cell assemblies, the first flow channel end plate is provided with a first arch-like flow channel and a second arch-like flow channel, the second flow channel end plate is provided with a third arch-like flow channel and a fourth arch-like flow channel, each of the first arch-like flow channel, the second arch-like flow channel, the third arch-like flow channel and the fourth arch-like flow channel is provided with a flow channel aperture, each flow channel aperture is in communication with the at least three hermetically-assembled cell assemblies, an electrolyte in the first arch-like flow channel flows through the at least three hermetically-assembled cell assemblies via the flow channel aperture in the first arch-like flow channel to the second arch-like flow channel, and an electrolyte in the third arch-like flow channel flows through the at least three hermetically-assembled cell assemblies via the flow channel aperture in the third arch-like flow channel to the fourth arch-like flow channel.

In another aspect, the present disclosure provides in some embodiments a flow battery including the above-mentioned cell stack.

The present disclosure at least has the above-mentioned beneficial effects.

According to the embodiments of the present disclosure, the cell stack includes: the first end plate; the second end plate; and the at least one cell module arranged between the first end plate and the second end plate. Each cell module includes the first flow channel end plate, the second flow channel end plate arranged opposite to the first flow channel end plate, and the single-cell assemblies arranged between the first flow channel end plate and the second flow channel end plate. The single-cell assemblies include at least three hermetically-assembled cell assemblies, the first flow channel end plate is provided with the first arch-like flow channel and the second arch-like flow channel, the second flow channel end plate is provided with the third arch-like flow channel and the fourth arch-like flow channel, each of the first arch-like flow channel, the second arch-like flow channel, the third arch-like flow channel and the fourth arch-like flow channel is provided with the flow channel aperture, each flow channel aperture is in communication with the at least three hermetically-assembled cell assemblies, the electrolyte in the first arch-like flow channel flows through the at least three hermetically-assembled cell assemblies via the flow channel aperture in the first arch-like flow channel to the second arch-like flow channel, and the electrolyte in the third arch-like flow channel flows through the at least three hermetically-assembled cell assemblies via the flow channel aperture in the third arch-like flow channel to the fourth arch-like flow channel. As a result, it is able to increase a length of an electrode in the flow battery along with an increase in the quantity of flow channel apertures, adjust the length of the electrode randomly in the case of same output power and a same area of the electrode, and narrow a path of the electrolyte flowing through the electrode, thereby to improve the electric energy conversion efficiency and improve the sealability of the flow channels.

The present disclosure will be described hereinafter in conjunction with the drawings and embodiments. The following embodiments are for illustrative purposes only, but shall not be used to limit the scope of the present disclosure. Actually, the embodiments are provided so as to facilitate the understanding of the scope of the present disclosure.

As shown in <FIG>, the present disclosure provides in some embodiments a cell stack of a flow battery, which includes: a first end plate <NUM>; a second end plate <NUM>; and at least one cell module arranged between the first end plate <NUM> and the second end plate <NUM>. Each cell module includes a first flow channel end plate <NUM>, a second flow channel end plate <NUM> arranged opposite to the first flow channel end plate <NUM>, and single-cell assemblies <NUM> arranged between the first flow channel end plate <NUM> and the second flow channel end plate <NUM>. The single-cell assemblies <NUM> include at least three hermetically-assembled cell assemblies, the first flow channel end plate <NUM> is provided with a first arch-like flow channel <NUM> and a second arch-like flow channel <NUM>, the second flow channel end plate <NUM> is provided with a third arch-like flow channel <NUM> and a fourth arch-like flow channel <NUM>, each of the first arch-like flow channel <NUM>, the second arch-like flow channel <NUM>, the third arch-like flow channel <NUM> and the fourth arch-like flow channel <NUM> is provided with a flow channel aperture, each flow channel aperture is in communication with the at least three hermetically-assembled cell assemblies, an electrolyte in the first arch-like flow channel <NUM> flows through the at least three hermetically-assembled cell assemblies via the flow channel aperture in the first arch-like flow channel <NUM> to the second arch-like flow channel <NUM>, and an electrolyte in the third arch-like flow channel <NUM> flows through the at least three hermetically-assembled cell assemblies via the flow channel aperture in the third arch-like flow channel <NUM> to the fourth arch-like flow channel <NUM>.

According to the embodiments of the present disclosure, it is able to increase a length of an electrode in the flow battery along with an increase in the quantity of flow channel apertures, adjust the length of the electrode randomly in the case of same output power and a same area of the electrode, and narrow a path of the electrolyte flowing through the electrode, thereby to improve the electric energy conversion efficiency and improve the sealability of the flow channels.

As shown in <FIG> and <FIG>, in a possible embodiment of the present disclosure, the flow channel apertures include a first flow channel aperture <NUM> formed in the first arch-like flow channel <NUM>, a second flow channel aperture <NUM> formed in the second arch-like flow channel <NUM>, a third flow channel aperture <NUM> formed in the third arch-like flow channel <NUM>, and a fourth flow channel aperture <NUM> formed in the fourth arch-like flow channel <NUM>. When a positive electrolyte is injected into the first arch-like flow channel <NUM> in the first flow channel end plate <NUM>, a negative electrolyte is injected into the third arch-like flow channel <NUM> in the second flow channel end plate <NUM>. In contrast, when the negative electrolyte is injected into the first arch-like flow channel <NUM> in the first flow channel end plate <NUM>, the positive electrolyte is injected into the third arch-like flow channel <NUM> in the second flow channel end plate <NUM>.

In the embodiments of the present disclosure, after the positive electrolyte has been injected into the first arch-like flow channel <NUM> in the first flow channel end plate <NUM>, the positive electrolyte flows into the at least three hermetically-assembled cell assemblies via the first flow channel aperture <NUM>, and then flows into the second arch-like flow channel <NUM> via the second flow channel aperture <NUM>. After the negative electrolyte has been injected into the third arch-like flow channel <NUM> in the second flow channel end plate <NUM>, the negative electrolyte flows into the at least three hermetically-assembled cell assemblies via the second flow channel aperture <NUM>, and then flows into the fourth arch-like flow channel <NUM> via the fourth flow channel aperture <NUM>.

In a possible embodiment of the present disclosure, the first end plate <NUM> is provided with a plurality of first via-holes <NUM>, and the second end plate <NUM> is provided with a plurality of second via-holes <NUM> corresponding to the first via-holes <NUM> respectively. Each fastening beam assembly <NUM> passes through the first via-hole <NUM> and the corresponding second via-hole <NUM>, so as to fix the first end plate <NUM>, the second end plate <NUM> and the at least one cell module.

In the embodiments of the present disclosure, the first via-hole is formed at an edge of an end surface of the first end plate <NUM>. The fastening beam assembly <NUM> is a screw rod with nuts at both ends. The screw rod passes through the first via-hole <NUM> and the second via-hole <NUM>, and then the nut is screwed in so as to fasten the first end plate <NUM> and the second end plate <NUM>.

In a possible embodiment of the present disclosure, the flow channel aperture is formed in an end flow channel of each of the first arch-like flow channel <NUM> and the second arch-like flow channel <NUM>. An end flow channel <NUM> of the first arch-like flow channel <NUM> and an end flow channel <NUM> of the second arch-like flow channel <NUM> are arranged at upper and lower sides of the first flow channel end plate <NUM> respectively.

The third arch-like flow channel <NUM> is arranged opposite to the first arch-like flow channel <NUM>, and the flow channel aperture in the third arch-like flow channel <NUM> is arranged at a position not opposite to the aperture in the first arch-like flow channel <NUM>. The fourth arch-like flow channel <NUM> is arranged opposite to the second arch-like flow channel <NUM>, and the flow channel aperture in the fourth arch-like flow channel <NUM> is arranged at a position not opposite to the flow channel aperture in the second arch-like flow channel <NUM>. An inlet end <NUM> of the first arch-like flow channel <NUM> and an inlet end <NUM> of the third arch-like flow channel <NUM> are in communication with an external inlet pipe, and an outlet end <NUM> of the second arch-like flow channel <NUM> and an outlet end <NUM> of the fourth arch-like flow channel <NUM> are in communication with an external outlet pipe. Each of the first arch-like flow channel <NUM>, the second arch-like flow channel <NUM>, the third arch-like flow channel <NUM> and the fourth arch-like flow channel <NUM> is provided with a closed end.

In the embodiments of the present disclosure, the first flow channel end plate <NUM> is of a same structure as the second flow channel end plate <NUM>. In use, after the first flow channel end plate <NUM> has been fixed, the second flow channel end plate <NUM> needs to be rotated by <NUM>° to be arranged opposite to the first flow channel end plate <NUM>. After the first end plate <NUM> is arranged opposite to the second end plate <NUM>, the first flow channel end plate <NUM> is fixedly coupled to the first end plate <NUM> through a first positioning pin, and the second flow channel end plate <NUM> is fixedly coupled to the second end plate <NUM> through a second positioning pin.

In the embodiments of the present disclosure, the flow channel apertures are formed at the upper and lower sides of the flow channel end plate, so that the electrolyte flows from one side to the other side after it enters the at least three hermetically-assembled cell assemblies. When the flow channel aperture is arranged at a position not opposite to the other flow channel aperture, it means that an orthogonal projection of the first flow channel aperture <NUM> onto the second flow channel end plate <NUM> does not overlap with the third flow channel arch-like aperture <NUM>, and an orthogonal projection of the second flow channel aperture <NUM> onto the second flow channel end plate <NUM> does not overlap with the fourth flow channel aperture <NUM>, in the case that the second flow channel end plate <NUM> is rotated by <NUM>° to be arranged opposite to the first flow channel end plate <NUM>, the first arch-like flow channel <NUM> is arranged opposite to the third arch-like flow channel <NUM> and the second arch-like flow channel <NUM> is arranged opposite to the fourth arch-like flow channel <NUM>.

As shown in <FIG>, in a possible embodiment of the present disclosure, the at least three hermetically-assembled cell assemblies include a first assembly <NUM>, a second assembly <NUM> hermetically assembled with the first assembly <NUM>, and at least one third assembly <NUM> arranged between the first assembly <NUM> and the second assembly <NUM>. The first assembly <NUM>, the second assembly <NUM> and the at least one third assembly <NUM> are hermetically assembled. The first assembly is arranged close to, and hermetically assembled with, the first flow channel end plate <NUM>, and the second assembly <NUM> is arranged closed to, and hermetically assembled with, the second flow channel end plate <NUM>.

In the embodiments of the present disclosure, the first assembly <NUM> is fixedly coupled to the first flow channel end plate <NUM>, the second assembly <NUM> is fixedly coupled to the second flow channel end plate <NUM>, and the quantity of third assemblies <NUM> is determined according to the practical need.

As shown in <FIG>, in a possible embodiment of the present disclosure, the first assembly <NUM> includes a first bipolar plate <NUM>, a first electrode <NUM>, a first outer frame <NUM>, a first separator <NUM>, a second electrode <NUM>, a second outer frame <NUM>, a first inner frame <NUM> and a second inner frame <NUM>. The first outer frame <NUM> is sleeved onto the first electrode <NUM>, a first installation platform <NUM> is arranged on a first end surface of the first outer frame <NUM>, and the first bipolar plate <NUM> is fixed onto the first installation platform <NUM>. The first inner frame <NUM> is sleeved onto the first electrode <NUM>, and a second end surface of the first inner frame <NUM> is attached to a second end surface of the first outer frame <NUM>. The first outer frame <NUM> is assembled with the first inner frame <NUM>, so as to form a plurality of first cavities in communication with the first electrode <NUM>. The first separator <NUM> is arranged between the first electrode <NUM> and the second electrode <NUM>, and coupled to the first electrode <NUM>, the second electrode <NUM>, a first end surface of the first inner frame <NUM> and a first end surface of the second outer frame <NUM>. Each of the second inner frame <NUM> and the second outer frame <NUM> is sleeved onto the second electrode <NUM>. A second end surface of the second inner frame <NUM> is attached to a second end surface of the second outer frame <NUM>. The second outer frame <NUM> is assembled with the second inner frame <NUM> so as to form a plurality of second cavities in communication with the second electrode <NUM>.

In the embodiments of the present disclosure, the first bipolar plate <NUM> is fixedly coupled to the first installation platform <NUM> through laser welding, a hot-melt film, or an adhesive. Polarity of the first electrode <NUM> is opposite to polarity of the second electrode <NUM>, i.e., when the first electrode <NUM> is positive, the second electrode <NUM> is negative. The first separator <NUM> is fixedly coupled to the first end surface of the first inner frame <NUM> and the first end surface of the second outer frame <NUM> through laser welding, a hot-melt film, or an adhesive, so as to be fixed between the first electrode <NUM> and the second electrode <NUM>. The first separator <NUM> is used to separate the electrolyte flowing to the first electrode <NUM> from the electrolyte flowing to the second electrode <NUM>, thereby to prevent the electrolyte flowing via the first cavity to the first electrode <NUM> from flowing to the second electrode <NUM>.

Through the first cavity, after the first inner frame <NUM> is hermetically assembled with the first outer frame <NUM>, the electrolyte at the second end surface of the first outer frame <NUM> merely flows to the first electrode <NUM> via the first cavity. Identically, the electrolyte at the second end surface of the second outer frame <NUM> merely flows to the second electrode <NUM> via the second cavity.

As shown in <FIG>, in a possible embodiment of the present disclosure, the first assembly <NUM> further includes a first current collector <NUM> in contact with the first bipolar plate <NUM>.

In the embodiments of the present disclosure, the first current collector <NUM> is a metal foil made of copper for collecting a current. A length of the first current collector <NUM> needs to be greater than a length of the first outer frame <NUM>, and one end of the first current collector <NUM> extends through one end of the first outer frame <NUM> so as to be coupled to an external power source.

In a possible embodiment of the present disclosure, all side walls on the second end surface of the first outer frame <NUM> and the second end surface of the second outer frame <NUM> are each of a double-wall structure, and all side walls on the first end surface of the first outer frame <NUM> and the first end surface of the second outer frame <NUM> are each of a single-wall structure for the hermetically assembling with the double-wall structure. The first end surface of the first outer frame <NUM> is fixedly coupled to the first flow channel end plate <NUM>, the second end surface of the first outer frame <NUM> is fixedly coupled to the first end surface of the second outer frame <NUM>, and the first end surface of the second outer frame <NUM> is fixedly coupled to the third assembly <NUM>.

In the embodiments of the present disclosure, the double-wall structure refers to that the side wall is of a double-layer structure. Taking the second outer frame <NUM> as an example, as shown in <FIG> which is a sectional view of the second outer frame <NUM> at a fourth inlet flow channel <NUM> and a third inlet flow channel <NUM>, side walls <NUM> and <NUM> at two sides of the fourth inlet flow channel <NUM> are each of a double-layer structure consisting of a first side wall <NUM> and a second side wall <NUM>, and a groove is formed between the first side wall <NUM> and the second side wall <NUM>, where <NUM> represents the second end surface of the second outer frame <NUM>, and <NUM> represents the first end surface of the second outer frame <NUM>.

In <FIG>, <NUM> represents the third inlet flow channel, and <NUM> and <NUM> represent side walls at two sides of the third inlet flow channel <NUM>, and each of the side walls <NUM> and <NUM> is of a single-wall structure. The side wall <NUM> is adapted to the groove between the first side wall <NUM> and the second side wall <NUM> for hermetical engagement.

During the assembling, the second end surface of the first outer frame <NUM> is fixedly coupled to the first end surface of the second outer frame <NUM> through the single-wall structure on the first end surface of the second outer frame <NUM> and the double-wall structure on the second end surface of the first outer frame <NUM>. Then, the electrolyte flows to the first electrode <NUM> via the plurality of first cavities, so that the entire first electrode <NUM> is immersed in the electrolyte quickly.

Identically, after the second end surface of the second outer frame <NUM> is fixedly coupled to the third assembly <NUM>, the electrolyte flows to the second electrode <NUM> via the plurality of second cavities, so that the entire second electrode <NUM> is immersed in the electrolyte quickly.

In the embodiments of the present disclosure, a first stopping column <NUM> is arranged on the first end surface of the first outer frame <NUM>, and a first stopping hole <NUM> is formed in the first flow channel end plate <NUM>. The first outer frame <NUM> is fixedly coupled to the first flow channel end plate <NUM> through the first stopping column <NUM> and the first stopping hole <NUM>.

As shown in <FIG>, in a possible embodiment of the present disclosure, the first outer frame <NUM> is provided with a plurality of first inlets <NUM> and a plurality of first outlets <NUM>, and the second outer frame <NUM> is provided with a plurality of second inlets <NUM> and a plurality of second outlets <NUM>. Each first inlet <NUM> is in communication with a corresponding second inlet <NUM>, and each first outlet <NUM> is in communication with a corresponding second outlet <NUM>. Each first inlet <NUM> is arranged at a position corresponding to, and in communication with, the flow channel aperture in the first arch-like flow channel <NUM>. The first outlet <NUM> is arranged at a position corresponding to, and in communication with, the flow channel aperture in the second arch-like flow channel <NUM>.

The second end surface of the first outer frame <NUM> is provided with a plurality of first electrolyte-intake blocking aperture <NUM> and a plurality of first electrolyte-outtake blocking aperture <NUM>, and the second outer frame <NUM> is further provided with a plurality of inlets <NUM> and a plurality of third outlets <NUM>. Each third inlet <NUM> is in communication with a corresponding first electrolyte-intake blocking aperture <NUM>, and arranged at a position corresponding to the flow channel aperture in the third arch-like flow channel <NUM>. The third outer <NUM> is in communication with the first electrolyte-outtake blocking aperture <NUM>, and arranged at a position corresponding to the flow channel aperture in the fourth arch-like flow channel <NUM>.

A first annular groove <NUM> is formed at a periphery of each of the first inlets <NUM> and the first outlets <NUM> in the first end surface of the first outer frame <NUM>, a second annular groove <NUM> is formed at a periphery of each of the first electrolyte-intake blocking apertures <NUM> and the first electrolyte-outtake blocking apertures <NUM>, a third annular groove <NUM> is formed at a periphery of each of the third inlets <NUM> and the third outlets <NUM> in the first end surface of the second outer frame <NUM>, and a fourth annular groove <NUM> is formed at a periphery of each of the second inlets <NUM> and the second outlets <NUM> in the second end surface of the second outer frame <NUM>.

In the embodiments of the present disclosure, side walls of the annular grooves in the second end surface of the first outer frame <NUM> and the second end surface of the second outer frame <NUM> are each of a double-wall structure, and side walls of the annular grooves in the first end surface of the first output frame <NUM> and the first end surface of the second outer frame <NUM> are each of a single-wall structure. Due to the first annular groove <NUM>, after the first flow channel end plate <NUM>, the first outer frame <NUM> and the second outer frame <NUM> are assembled together, the first flow channel aperture <NUM> is in direct, hermetical communication with the corresponding first inlet <NUM>, and the second flow channel aperture <NUM> is in direct, hermetical communication with the corresponding first outlet <NUM>. At this time, the electrolyte from the first flow channel aperture <NUM> flows to the second end surface, rather than the first end surface, of the first outer frame <NUM>. Identically, the electrolyte from the first outlet <NUM> flows through the second flow channel <NUM> to the second arch-like flow channel <NUM> rather than to the first end surface of the first outer frame <NUM>. In addition, during the assembling of the first outer frame <NUM> with the first flow channel end plate <NUM>, a first gasket <NUM> is arranged in the first annular groove <NUM>, so as to further prevent the electrolyte from flowing to the first end surface of the first outer frame <NUM>.

In the embodiments of the present disclosure, when the first outer frame <NUM> is fixedly coupled to the second outer frame <NUM>, the second annular groove <NUM> and the third annular groove <NUM> are engaged with each other through the single-wall structure and the double-wall structure so as to form a hermetical communication channel. At this time, the first electrolyte-intake blocking aperture <NUM> is in direct, hermetical communication with the third inlet <NUM> via the communication channel, and the first electrolyte-outtake blocking aperture <NUM> is also in direct, hermetical communication with the third outlet <NUM>. The first electrolyte-intake blocking aperture <NUM> and the first electrolyte-outtake blocking aperture <NUM> are each in a blocking state, so the electrolyte entering the third inlet <NUM> and the third outlet <NUM> flows merely on the second end surface of the second outer frame <NUM> rather than to any end surface of the first outer frame <NUM>.

In the embodiments of the present disclosure, due to the third annular groove <NUM>, the electrolyte on the second end surface of the second outer frame <NUM> does not flow through the second inlet <NUM> and the second outlet <NUM> to the first end surface of the second outer frame <NUM>. In addition, the electrolyte from the first flow channel aperture <NUM> directly flows through the second inlet <NUM> to the third assembly <NUM> without flowing to the second end surface of the second outer frame <NUM>. Furthermore, the electrolyte in the third assembly <NUM> flows through the second outlet <NUM> to the first end surface of the second outer frame <NUM> and directly flows through the first outlet <NUM> to the second arch-like flow channel <NUM> without flowing to the second end surface of the second outer frame <NUM>.

In a possible embodiment of the present disclosure, the first end surface of the first outer frame <NUM> is provided with a plurality of first flow channels <NUM>, and the second end surface of the first outer frame <NUM> is provided with a plurality of second inlet flow channels <NUM> and a plurality of second outlet flow channels <NUM>. Each second inlet flow channel <NUM> is in communication with one first inlet <NUM> and one first cavity, and each second outlet flow channel <NUM> is in communication with one first outlet <NUM> and one first cavity.

The first end surface of the second outer frame <NUM> is provided with a plurality of third inlet flow channels <NUM> and a plurality of third outlet flow channels <NUM>, each third inlet flow channel <NUM> is in communication with one second inlet <NUM>, and each third outlet flow channel <NUM> is in communication with one second outlet <NUM>.

The second end surface of the second outer frame <NUM> is provided with a plurality of fourth inlet flow channels <NUM> and a plurality of fourth outlet flow channels <NUM>, each fourth inlet flow channel <NUM> is in communication with one third inlet <NUM> and one second cavity, and each fourth outlet flow channel <NUM> is in communication with one third outlet <NUM> and one second cavity.

In the embodiments of the present disclosure, side walls of the flow channels on the second end surface of the first outer frame <NUM> and the second end surface of the second outer frame <NUM> are each of a double-wall structure, and side walls of the flow channels on the first end surface of the first outer frame <NUM> and the first end surface of the second outer frame <NUM> are each of a single-wall structure. Each first flow channel <NUM> on the first outer frame <NUM> functions as a support, so as to prevent the first outer frame <NUM> from being damaged during the fastening. After the first outer frame <NUM> has been assembled with the second outer frame <NUM>, the second inlet flow channel <NUM> is engaged with the corresponding third inlet flow channel <NUM> through the single-wall structure and the double-wall structure, so as to form a first hermetical flow channel. At this time, the first inlet <NUM> in the second end surface of the first outer frame <NUM>, the second inlet <NUM> in the second end surface of the second outer frame <NUM> and the first cavity are in communication with each other via the first hermetical flow channel, so the electrolyte from the first flow channel aperture <NUM> directly flows to the first electrode <NUM> and the second inlet <NUM>.

Identically, the second outlet flow channel <NUM> is engaged with the corresponding third outlet flow channel <NUM> to form a second hermetical flow channel. At this time, the first outlet <NUM> in the second end surface of the first outer frame <NUM>, the second outlet <NUM> in the second end surface of the second outer frame <NUM> and the first cavity are in communication with each other via the second hermetical flow channel, so the electrolyte from the first electrode <NUM> merely flows through the first cavity to the first outlet <NUM> or the second outlet <NUM>, and the electrolyte entering the first outlet <NUM> directly flows to the second arch-like flow channel <NUM>.

As shown in <FIG>, in a possible embodiment of the present disclosure, the second assembly <NUM> includes a second bipolar plate <NUM>, a third outer frame <NUM> sleeved onto the second bipolar plate <NUM>, and a second current collector <NUM> in contact with the second bipolar plate <NUM>. Side walls on a second end surface of the third outer frame <NUM> are each of a double-wall structure, and side walls on a first end surface of the third outer frame <NUM> are each of a single-wall structure adapted to the double-wall structure. The second end surface of the third outer frame <NUM> is fixedly coupled to the second flow channel end plate <NUM>, and the first end surface of the third outer frame <NUM> is fixedly coupled to the third assembly <NUM>.

In the embodiments of the present disclosure, the second current collector <NUM> is a metal foil for collecting a current, and it is arranged between the second end surface of the third outer frame <NUM> and the second flow channel end plate <NUM>. A length of the second current collector <NUM> needs to be greater than a length of the third outer frame <NUM>, and one end of the second current collector <NUM> extends through one end of the third outer frame <NUM> so as to be coupled to an external power source.

In the embodiments of the present disclosure, a second stopping column <NUM> is arranged on the second end surface of the third outer frame <NUM>, and a corresponding second stopping hole is formed in the second flow channel end plate <NUM>. The third outer frame <NUM> is fixedly coupled to the second flow channel end plate <NUM> through the second stopping column <NUM> and the second stopping hole.

In a possible embodiment of the present disclosure, the third outer frame <NUM> is provided with a plurality of fourth inlets <NUM> and a plurality of fourth outlets <NUM>, and the first end surface of the third outer frame <NUM> is provided with a plurality of second electrolyte-intake blocking apertures <NUM> and a plurality of second electrolyte-outtake blocking apertures <NUM>. Each fourth inlet <NUM> is arranged at a position corresponding to, and in communication with, the flow channel aperture in the third arch-like flow channel <NUM>, and each fourth outlet <NUM> is arranged at a position corresponding to, and in communication with, the flow channel aperture in the fourth arch-like flow channel <NUM>. The second electrolyte-intake blocking aperture <NUM> is arranged at a position corresponding to the flow channel aperture in the first arch-like flow channel <NUM>, and the second electrolyte-outtake blocking aperture <NUM> is arranged at a position corresponding to the flow channel aperture in the second arch-like flow channel <NUM>. A fifth annular groove <NUM> is formed at a periphery of each of the fourth inlets <NUM> and the fourth outlets <NUM> in the second end surface of the third outer frame <NUM>, and a sixth annular groove <NUM> is formed at a periphery of each of the second electrolyte-intake blocking apertures <NUM> and the second electrolyte-outtake blocking apertures <NUM> in the first end surface of the third outer frame <NUM>.

In the embodiments of the present disclosure, through the fifth annular groove <NUM> in the second end surface of the third outer frame <NUM>, the third flow channel aperture <NUM> is in direct, hermetical communication with the fourth inlet <NUM>, and the fourth flow channel aperture <NUM> is in direct, hermetical communication with the fourth outlet <NUM>. At this time, the electrolyte from the third flow channel aperture <NUM> directly flows to the first end surface of the third outer frame <NUM> rather than to the second end surface of the third outer frame <NUM>. Identically, the electrolyte from the fourth outlet <NUM> directly flows through the fourth flow channel aperture <NUM> to the fourth arch-like flow channel <NUM> rather than to the second end surface of the third outer frame <NUM>. In addition, during the assembling of the third outer frame <NUM> with the second flow channel end plate <NUM>, a second gasket <NUM> is provided in the fifth annular groove <NUM> in the second end surface of the third outer frame <NUM>, so as to further prevent the electrolyte from flowing to the second end surface of the third outer frame <NUM>.

In the embodiments of the present disclosure, side walls of the annular grooves in the first end surface of the third outer frame <NUM> are each of a single-wall structure. Due to the second electrolyte-intake blocking aperture <NUM>, the second electrolyte-outtake blocking aperture <NUM> and the sixth annular groove <NUM>, after the third outer frame <NUM> has been assembled with the third assembly <NUM>, the second electrolyte-intake blocking aperture <NUM> and the second electrolyte-outtake blocking aperture <NUM> are in direct communication with the third assembly <NUM>. In addition, due to the blocking at the bottom, the electrolyte flowing from the third assembly <NUM> into the sixth annular groove <NUM> does not flow to any end surface of the outer frame <NUM>.

In a possible embodiment of the present disclosure, the second end surface of the third outer frame <NUM> is provided with a plurality of fifth flow channels <NUM>, the first end surface of the third outer frame <NUM> is provided with a plurality of sixth inlet flow channels <NUM> and a plurality of sixth outlet flow channels <NUM>, each sixth inlet flow channel <NUM> is in communication with one fourth inlet <NUM>, and each sixth outlet flow channel is in communication with one fourth outlet <NUM>.

In the embodiments of the present disclosure, side walls of the flow channels on the first end surface of the third outer frame <NUM> are each of a double-wall structure. The fifth flow channel <NUM> on the third outer frame <NUM> functions as a support, so as to prevent the third outer frame <NUM> from being damaged during the fastening. Due to the sixth inlet flow channel <NUM>, the electrolyte from the third flow channel aperture <NUM> merely flows to the third assembly <NUM>, and due to the sixth outlet flow channel <NUM>, the electrolyte in the sixth outlet flow channel <NUM> merely flows through the fourth outlet <NUM> to the fourth flow channel aperture <NUM>.

As shown in <FIG>, in a possible embodiment of the present disclosure, the third assembly <NUM> includes a fourth bipolar plate <NUM>, a fifth electrode <NUM>, a fifth outer frame <NUM>, a third separator <NUM>, a sixth electrode <NUM>, a sixth outer frame <NUM>, a fifth inner frame <NUM> and a sixth inner frame <NUM>. The fifth outer frame <NUM> is sleeved onto the fifth electrode <NUM>, a first end surface of the fifth outer frame <NUM> is provided with a third installation platform <NUM>, and the fourth bipolar plate <NUM> is fixed on the third installation platform <NUM>. The fifth inner frame <NUM> is sleeved onto the fifth electrode <NUM>, and the second end surface of the fifth inner frame <NUM> is attached to the second end surface of the fifth outer frame <NUM>. The fifth outer frame <NUM> is assembled with the fifth inner frame <NUM> to form a plurality of fourth cavities in communication with the fifth electrode <NUM>. The third separator <NUM> is arranged between the fifth electrode <NUM> and the sixth electrode <NUM>, and coupled to the fifth electrode <NUM>, the sixth electrode <NUM>, the first end surface of the fifth inner frame <NUM> and a first end surface of the sixth outer frame <NUM>. Each of the fifth inner frame <NUM> and the sixth outer frame <NUM> is sleeved onto the sixth electrode <NUM>. A second end surface of the sixth inner frame <NUM> is attached to a second end surface of the sixth outer frame <NUM>, and the sixth outer frame <NUM> is assembled with the sixth inner frame <NUM> to form a plurality of fifth cavities in communication with the sixth electrode <NUM>.

In the embodiments of the present disclosure, one or more third assemblies <NUM> is provided. In the case of a plurality of third assemblies <NUM>, the first end surface of the fifth outer frame <NUM> of the current third assembly <NUM> is attached to the second end surface of the sixth outer frame <NUM> of the previous third assembly <NUM>.

The fourth bipolar plate <NUM> is fixedly coupled to the third installation platform <NUM> through laser welding, a hot-melt film, or an adhesive. Polarity of the fifth electrode <NUM> is opposite to polarity of the sixth electrode <NUM>, and identical to the polarity of the first electrode <NUM>. The third separator <NUM> is fixedly coupled to the first end surface of the fifth inner frame <NUM> and the sixth end surface of the second outer frame <NUM> through laser welding, a hot-melt film, or an adhesive, so as to be fixed between the fifth electrode <NUM> and the sixth electrode <NUM>. The third separator <NUM> is used to separate the electrolyte flowing to the fifth electrode <NUM> from the electrolyte flowing to the sixth electrode <NUM>, thereby to prevent the electrolyte flowing via the fourth cavity to the fifth electrode <NUM> from flowing to the sixth electrode <NUM>.

Through the fourth cavity, after the fifth inner frame <NUM> is hermetically assembled with the fifth outer frame <NUM>, the electrolyte at the second end surface of the fifth outer frame <NUM> merely flows to the fifth electrode <NUM> via the fourth cavity. Identically, the electrolyte at the second end surface of the sixth outer frame <NUM> merely flows to the sixth electrode <NUM> via the fifth cavity.

As shown in <FIG>, in a possible embodiment of the present disclosure, side walls on the second end surface of the fifth outer frame <NUM> and the second end surface of the sixth outer frame <NUM> are each of a double-wall structure, and side walls on the first end surface of the fifth outer frame <NUM> and the first end surface of the sixth outer frame <NUM> are each of a single-wall structure adapted to the double-wall structure. The second end surface of the fifth outer frame <NUM> is fixedly coupled to the first end surface of the sixth outer frame <NUM>, the first end surface of the fifth outer frame <NUM> is fixedly coupled to the second end surface of the second outer frame <NUM>, and the second end surface of the sixth outer frame <NUM> is fixedly coupled to the first end surface of the third outer frame <NUM>.

In the embodiments of the present disclosure, during the assembling of the cell stack of the flow battery, the second end surface of the sixth outer frame <NUM> is engaged with the first end surface of the third outer frame <NUM> through the single-wall structure and the double-wall structure. The first end surface of the sixth inner frame <NUM> is fixedly coupled to the second bipolar plate through laser welding, a hot-melt film or an adhesive. The second end surface of the fifth outer frame <NUM> is engaged with the first end surface of the sixth outer frame <NUM> through the single-wall structure and the double-wall structure, and the first end surface of the fifth outer frame <NUM> is engaged with the second end surface of the second outer frame <NUM> through the single-wall structure and the double-wall structure.

Identically, after the first end surface of the fifth outer frame <NUM> has been fixedly coupled to the second end surface of the second outer frame <NUM>, the electrolyte on the second end surface of the second outer frame <NUM> flows to the fifth electrode <NUM> via the plurality of fourth cavities, so that the entire fifth electrode <NUM> is immersed in the electrolyte quickly.

Identically, after the second end surface of the sixth outer frame <NUM> has been fixedly coupled to the first end surface of the third outer frame <NUM>, the electrolyte on the second end surface of the sixth outer frame <NUM> flows to the sixth electrode <NUM> via the plurality of fifth cavities, so that the entire sixth electrode <NUM> is immersed in the electrolyte quickly.

In a possible embodiment of the present disclosure, the fifth outer frame <NUM> is provided with a plurality of seventh inlets <NUM>, a plurality of seventh outlets <NUM>, a plurality of eighth inlets <NUM> and a plurality of eighth outlets <NUM>. Each seventh inlet <NUM> is arranged at a position corresponding to the flow channel aperture in the first arch-like flow channel <NUM>, each seventh outlet <NUM> is arranged at a position corresponding to the flow channel aperture in the second arch-like flow channel <NUM>, each eighth inlet <NUM> is arranged at a position corresponding to the flow channel aperture in the third arch-like flow channel <NUM>, and each eighth outlet <NUM> is arranged at a position corresponding to the flow channel aperture in the fourth arch-like flow channel <NUM>.

The sixth outer frame <NUM> is provided with a ninth inlet <NUM> arranged at a position corresponding to, and in communication with, the seventh inlet <NUM>, a ninth outlet <NUM> arranged at a position corresponding to, and in communication with, the seventh outlet <NUM>, a tenth inlet <NUM> arranged at a position corresponding to, and in communication with, the eighth inlet <NUM>, and a tenth outlet <NUM> arranged at a position corresponding to, and in communication with, the eighth outlet <NUM>.

An eighth annular groove <NUM> is formed at a periphery of each of the seventh inlets <NUM> and the seventh outlets <NUM> in the first end surface of the fifth outer frame <NUM>, a ninth annular groove <NUM> is formed at a periphery of each of the eighth inlets <NUM> and the eighth outlets <NUM> in the second end surface of the fifth outer frame <NUM>, a tenth annular groove <NUM> is formed at a periphery of each of the tenth inlets <NUM> and the tenth outlets <NUM> in the first end surface of the sixth outer frame <NUM>, and an eleventh annular groove <NUM> is formed at a periphery of each of the ninth inlets <NUM> and the ninth outlets <NUM> in the second end surface of the sixth outer frame <NUM>.

In the embodiments of the present disclosure, side walls of the annular grooves in the second end surface of the fifth outer frame <NUM> and the second end surface of the sixth outer frame <NUM> are ach of a double-wall structure, and side walls of the annular grooves in the first end surface of the fifth outer frame <NUM> and the first end surface of the sixth outer frame <NUM> are each of a single-wall structure. After the assembling, due to the ninth annular groove <NUM> in the second end surface of the fifth outer frame <NUM> and the tenth annular groove <NUM> in the first end surface of the sixth outer frame <NUM>, the eighth inlet <NUM> is in direct, hermetical communication with the tenth inlet <NUM>, and the eighth outlet <NUM> is in direct, hermetical communication with the tenth outlet <NUM>. At this time, the electrolyte on the second end surface of the sixth outer frame <NUM> directly flows to the first end surface of the fifth outer frame <NUM> rather than to the second end surface of the fifth outer frame <NUM> through the tenth inlet <NUM> and the tenth outlet <NUM>.

Due to the eighth annular groove <NUM> in the first end surface of the fifth outer frame <NUM> and the fourth annular groove <NUM> in the second end surface of the second outer frame <NUM>, the second inlet <NUM> is in direct, hermetical communication with the seventh inlet <NUM>, and the second outlet <NUM> is in direct, hermetical communication with the seventh outlet <NUM>. At this time, the electrolyte on the first end surface of the fifth outer frame <NUM> directly flows to the second end surface of the second outer frame <NUM>, rather than to the first end surface of the second outer frame <NUM> through the seventh inlet <NUM> and the seventh outlet <NUM>, or to the first end surface of the second outer frame <NUM> through the third inlet <NUM> and the third outlet <NUM> due to the first electrolyte-intake blocking aperture <NUM> and the first electrolyte-outtake blocking aperture <NUM>.

Due to the eleventh annular groove <NUM> in the second end surface of the sixth outer frame <NUM> and the sixth annular groove <NUM> in the first end surface of the third outer frame <NUM>, the ninth inlet <NUM> is in direct, hermetical communication with the second electrolyte-intake blocking aperture <NUM>, and the ninth outlet <NUM> is in direct, hermetical communication with the second electrolyte-outtake blocking aperture <NUM>. At this time, the electrolyte flows merely on the second end surface of the fifth outer frame <NUM>, rather than to the second end surface of the sixth outer frame <NUM> through the ninth inlet <NUM> and the ninth outlet <NUM>.

In the embodiments of the present disclosure, after the assembling of the cell stack of the flow battery, the first flow channel aperture <NUM> is in communication with the first inlet <NUM>, the second inlet <NUM>, the seventh inlet <NUM>, the ninth inlet <NUM> and the second electrolyte-intake blocking aperture <NUM>.

The second channel aperture <NUM> is in communication with the first outlet <NUM>, the second outlet <NUM>, the seventh outlet <NUM>, the ninth outlet <NUM> and the second electrolyte-outtake blocking aperture <NUM>. The second electrolyte-intake blocking aperture <NUM> and the second electrolyte-outtake blocking aperture <NUM> are used to block the electrolyte on the second end surface of the fifth outer frame <NUM> from flowing to the second end surface of the sixth outer frame <NUM>, and merely allow the electrolyte to flow through the seventh outlet <NUM> into the second arch-like flow channel <NUM>.

The third flow channel aperture <NUM> is in communication with the fourth inlet <NUM>, the tenth inlet <NUM>, the eighth inlet <NUM>, the third inlet <NUM> and the first electrolyte-intake blocking aperture <NUM>.

The fourth channel aperture <NUM> is in communication with the fourth outlet <NUM>, the tenth outlet <NUM>, the eighth outlet <NUM>, the third outlet <NUM> and the first electrolyte-outtake blocking aperture <NUM>. The first electrolyte-intake blocking aperture <NUM> and the first electrolyte-outtake blocking aperture <NUM> are mainly used to block the third inlet <NUM> and the third outlet <NUM> in the first end surface of the second outer frame <NUM>, so as to prevent the electrolyte on the second end surface of the second outer frame <NUM> from flowing to the first end surface of the second outer frame <NUM>, and merely allow the electrolyte to flow through the third outlet <NUM> into the fourth arch-like flow channel <NUM>.

In a possible embodiment of the present disclosure, the first end surface of the fifth outer frame <NUM> is provided with a plurality of ninth inlet flow channels <NUM> and a plurality of ninth outlet flow channels <NUM>, each ninth inlet flow channel <NUM> is in communication with one eighth inlet <NUM>, and each ninth outlet flow channel <NUM> is in communication with one eighth outlet <NUM>. The second end surface of the fifth outer frame <NUM> is provided with a plurality of tenth inlet flow channels <NUM> and a plurality of tenth outlet flow channels <NUM>, each tenth inlet flow channel <NUM> is in communication with one seventh inlet <NUM> and one fourth cavity, and each tenth outlet flow channel <NUM> is in communication with one seventh outlet <NUM> and one fourth cavity.

The first end surface of the sixth outer frame <NUM> is provided with a plurality of eleventh inlet flow channels <NUM> and a plurality of eleventh outlet flow channels <NUM>, each eleventh inlet flow channel <NUM> is in communication with one ninth inlet <NUM>, and each eleventh outlet flow channel <NUM> is in communication with one ninth outlet <NUM>. The second end surface of the sixth outer frame <NUM> is provided with a plurality of twelfth inlet flow channels <NUM> and a plurality of twelfth outlet flow channels <NUM>, each twelfth inlet flow channel <NUM> is in communication with one tenth inlet <NUM> and one fifth cavity, and each twelfth outlet flow channel <NUM> is in communication with one tenth outlet <NUM> and one fifth cavity.

In the embodiments of the present disclosure, side walls of the flow channels on the second end surface of the fifth outer frame <NUM> and the second end surface of the sixth outer frame <NUM> are each of a double-wall structure, and side walls of the flow channels on the first end surface of the fifth outer frame <NUM> and the first end surface of the sixth outer frame <NUM> are each of a single-wall structure. During the assembling of the sixth outer frame <NUM> with the third outer frame <NUM>, the twelfth inlet flow channel <NUM> is engaged with the sixth inlet flow channel <NUM> through the single-wall structure and the double-wall structure, so as to form a third hermetical flow channel. At this time, the tenth inlet <NUM> in the second end surface of the sixth outer frame <NUM>, the fourth inlet flow channel <NUM> in the first end surface of the third outer frame <NUM> and fifth cavity in communication with the twelfth inlet flow channel <NUM> are in communication with each other via the third hermetical flow channel, so the electrolyte from the third flow channel aperture <NUM> merely flows through the third hermetical flow channel to the tenth inlet <NUM> and the sixth electrode <NUM>.

Identically, the twelfth outlet flow channel <NUM> is engaged with the sixth outlet flow channel <NUM> to form a fourth hermetical flow channel. At this time, the tenth outlet <NUM> in the second end surface of the sixth outer frame <NUM>, the fourth outlet flow channel <NUM> in the first end surface of the third outer frame <NUM> and the fifth cavity in communication with the twelfth outlet flow channel <NUM> are in communication with each other via the fourth hermetical flow channel, so the electrolyte in the fourth hermetical flow channel merely flows into the tenth outlet <NUM> and the fourth outlet flow channel <NUM>, and the electrolyte in the fourth outlet flow channel <NUM> directly flows through the fourth flow channel aperture <NUM> into the fourth arch-like flow channel <NUM>.

Identically, after the fifth outer frame <NUM> has been assembled with the second outer frame <NUM>, the fifth inlet flow channel <NUM> is engaged with the fourth inlet flow channel <NUM> to form a fifth hermetical flow channel. At this time, the third inlet <NUM> in the second end surface of the second outer frame <NUM>, the eighth inlet <NUM> in the first end surface of the fifth outer frame <NUM> and the second cavity in communication with the fourth inlet flow channel <NUM> are in communication with each other via the fifth hermetical flow channel, so the electrolyte flowing into the fifth hermetical flow channel through the eighth inlet <NUM> merely flows to the third inlet <NUM> and the second electrode <NUM>, and the electrolyte in the third inlet <NUM> does not flow due to the first electrolyte-intake blocking aperture <NUM>.

Identically, the ninth outlet flow channel <NUM> is engaged with the fourth outlet flow channel <NUM> to form a sixth hermetical flow channel. At this time, the third outlet <NUM> in the second end surface of the second outer frame <NUM>, the eighth outlet <NUM> in the first end surface of the fifth outer frame <NUM> and the second cavity in communication with the fourth outlet flow channel <NUM> are in communication with each other via the sixth hermetical flow channel, so the electrolyte flowing from the second electrode <NUM> into the sixth hermetical flow channel merely flows into the third outlet <NUM> and the eighth outlet <NUM>, the electrolyte in the third outlet <NUM> does not flow due to the first electrolyte-outtake blocking aperture <NUM>, and the electrolyte in the eighth outlet <NUM> directly flows through the fourth flow channel aperture <NUM> into the second arch-like flow channel <NUM>.

Identically, after the assembling of the fifth outer frame <NUM> with the sixth outer frame <NUM>, the tenth inlet flow channel <NUM> is engaged with the eleventh inlet flow channel <NUM> to form a seventh hermetical flow channel. At this time, the seventh inlet <NUM> in the second end surface of the fifth outer frame <NUM>, the ninth inlet <NUM> in the first end surface of the sixth outer frame <NUM> and the fourth cavity in communication with the tenth inlet flow channel <NUM> are in communication with each other via the seventh hermetical flow channel, so the electrolyte flowing through the seventh inlet <NUM> into the seventh hermetical flow channel merely flows to the ninth inlet <NUM> and the fifth electrode <NUM>, and the electrolyte in the ninth inlet <NUM> does not flow due to the second electrolyte-intake blocking aperture <NUM>.

Identically, the tenth outlet flow channel <NUM> is engaged with the eleventh outlet flow channel <NUM> to form an eighth hermetical flow channel. At this time, the seventh outlet <NUM> in the second end surface of the fifth outer frame <NUM>, the ninth outlet <NUM> in the first end surface of the sixth outer frame <NUM> and the fourth cavity in communication with the tenth outlet flow channel <NUM> are in communication with each other via the eighth hermetical flow channel, so the electrolyte flowing from the fifth electrode <NUM> into the eighth hermetical flow channel merely flows into the ninth outlet <NUM> and the seventh outlet <NUM>, the electrolyte in the ninth outlet <NUM> does not flow due to the second electrolyte-outtake blocking aperture <NUM>, and the electrolyte in the seventh outlet <NUM> directly flows through the second flow channel aperture <NUM> into the second arch-like flow channel <NUM>.

As shown in <FIG>, in a possible embodiment of the present disclosure, each of the first cavity, the second cavity, the fourth cavity and the fifth cavity includes a first groove <NUM> and a second groove <NUM>. The first groove is formed in each of the second end surface of the first inner frame <NUM>, the second end surface of the second inner frame <NUM>, the second end surface of the fifth inner frame <NUM> and the second end surface of the sixth inner frame <NUM>, and the second groove <NUM> matching the first groove <NUM> is formed in each of the second end surface of the first outer frame <NUM>, the second end surface of the second outer frame <NUM>, the second end surface of the fifth outer frame <NUM> and the second end surface of the sixth outer frame <NUM>.

In the embodiments of the present disclosure, each of the first cavity, the second cavity, the fourth cavity and the fifth cavity is formed through the first groove <NUM> and the second groove <NUM>. In <FIG>, <NUM> represents the cavity formed through the first groove <NUM> and the second groove <NUM>, and the cavity is in communication with the electrode, so that the electrolyte flows via the cavity to the electrode.

In the embodiments of the present disclosure, the first inner frame <NUM> is of a completely same structure as the fifth inner frame <NUM>, the sixth inner frame <NUM> is of a completely same structure as the second inner frame <NUM>, and a groove <NUM> for fixing the bipolar plate is formed in each of the first end surface of the sixth inner frame <NUM> and the first end surface of the second inner frame <NUM>.

In a possible embodiment of the present disclosure, the inner frames and the outer frames are made of polypropylene, and the flow channel end plates are made of polyvinyl chloride. A first stopping groove <NUM> is further formed in the second end surface of each inner frame, and a first stopping rib <NUM> is formed on the second end surface of each outer frame. The outer frame is assembled with the corresponding outer frame through the engagement of the first stopping groove <NUM> with the first stopping rib <NUM>, so as to prevent the displacement of the inner frame and the outer frame. Each inner frame is further provided with a buffer table <NUM> between the cavity and the electrode, so as to reduce a flow rate of the electrolyte from the cavity, thereby to reduce an impact on the electrode.

A specific working principle of the cell stack of the flow battery will be described hereinafter. When the first electrode <NUM> is positive, the fifth electrode <NUM> is positive too, and the second electrode <NUM> and the sixth electrode <NUM> are negative. At this time, the positive electrolyte is injected into the first arch-like flow channel <NUM>, and the negative electrolyte is injected into the third arch-like flow channel <NUM>. After the positive electrolyte from the first flow channel aperture <NUM> flows to the second end surface of the first outer frame <NUM> and the second end surface of the fifth outer frame <NUM> through the first inlet <NUM> and the seventh inlet <NUM> respectively, and flows to the first electrode <NUM> and the fifth electrode <NUM> through the first hermetical flow channel and the seventh hermetical flow channel respectively. Next, the positive electrolyte flows into the second hermetical flow channel and the eighth hermetical flow channel, and flows to the second arch-like flow channel <NUM> through the first outlet <NUM> and the seventh outlet <NUM>.

In addition, the negative electrolyte from the third flow channel aperture <NUM> merely flows to the second end surface of the sixth outer frame <NUM> and the second end surface of the second outer frame <NUM> through the fourth inlet <NUM> and the eighth inlet <NUM> respectively, and flows to the sixth electrode <NUM> and the second electrode <NUM> through the third hermetical flow channel and the fifth hermetical flow channel respectively. Next, the negative electrolyte flows into the fourth hermetical flow channel and the sixth hermetical flow channel, and then flows into the fourth arch-like flow channel <NUM> through the fourth outlet <NUM> and the eighth outlet <NUM>.

The second electrode <NUM> and the sixth electrode <NUM> are immersed in the electrolyte, and then the electrolyte flows into the fourth arch-like flow channel <NUM> through the tenth outlet <NUM> and the third outlet <NUM>.

According to the cell stack of the flow battery in the embodiments of the present disclosure, the electrolyte flows to the electrode at a large flow through increasing the quantity of the inlet flow channels and the outlet flow channels in the case that the electrode is too long. As a result, in the case of same power and a same area of the electrode, it is able to reduce a flow resistance of the electrolyte through increasing a length of the electrode and decreasing a width of the electrode, and reduce the power consumption of a pump, thereby to increase the electric energy conversion efficiency.

The present disclosure further provides in some embodiments a flow battery which includes at least one of the above-mentioned cell stack.

According to the flow battery in the embodiments of the present disclosure, it is able to increase the power through a plurality of cell stacks, thereby to meet the requirement on the large power.

Claim 1:
A cell stack of a flow battery, comprising:a first end plate (<NUM>); a second end plate (<NUM>); and at least one cell module arranged between the first end plate (<NUM>) and the second end plate (<NUM>), wherein each cell module comprises a first flow channel end plate (<NUM>), a second flow channel end plate (<NUM>) arranged opposite to the first flow channel end plate (<NUM>), and single-cell assemblies arranged between the first flow channel end plate (<NUM>) and the second flow channel end plate (<NUM>), wherein the single-cell assemblies comprise at least three hermetically-assembled cell assemblies, the first flow channel end plate (<NUM>) is provided with a first arch-like flow channel (<NUM>) and a second arch-like flow channel (<NUM>);the second flow channel end plate (<NUM>) is provided with a third arch-like flow channel (<NUM>) and a fourth arch-like flow channel (<NUM>);
each of the first arch-like flow channel (<NUM>), the second arch-like flow channel (<NUM>), the third arch-like flow channel (<NUM>) and the fourth arch-like flow channel (<NUM>) is provided with a flow channel aperture (<NUM>, <NUM>, <NUM>, <NUM>);
characterized in that each flow channel aperture (<NUM>, <NUM>, <NUM>, <NUM>) is in communication with the at least three hermetically-assembled cell assemblies;an electrolyte in the first arch-like flow channel (<NUM>) flows through the at least three hermetically-assembled cell assemblies via the flow channel aperture (<NUM>) in the first arch-like flow channel (<NUM>) to the second arch-like flow channel (<NUM>); and
an electrolyte in the third arch-like flow channel (<NUM>) flows through the at least three hermetically-assembled cell assemblies via the flow channel aperture (<NUM>, <NUM>, <NUM>, <NUM>) in the third arch-like flow channel (<NUM>) to the fourth arch-like flow channel (<NUM>).