TANKS EMBODIMENT FOR A FLOW BATTERY

Abstract

A flow battery of the type comprising at least one stack of planar cells 17, at least one negative electrolyte tank 3, at least one positive electrolyte tank 4, at least two pumps 5 and 6, for supplying electrolytes to at least one stack of planar cells 17. Either or both of the first tank 3 and the second tank 4, a primary cabinet 19, an underground tanks container 20, having a thermal insulation 18 between said tanks container 20 and the tanks 3 and 4, at least one secondary heat exchanger 21, at least one primary heat exchanger 22, at least one coolant pump 23, wherein said container 20 is buried below ground level.

Claims

1. A flow battery, comprising: at least one stack 17, at least one negative electrolyte tank 3, at least one positive electrolyte tank 4; at least two pumps 5 and 6; a primary cabinet 19; an underground container for the tanks 20; a thermal insulation 18 between said tanks 3 and 4 and said container 20 and between said tanks 3 and 4; at least one secondary heat exchanger 21; at least one primary heat exchanger 22; at least one coolant pump 23; and wherein said underground tank container 20 is buried below ground level; and wherein said primary cabinet 19 is disposed above ground level.

2. The flow battery according to claim 1, wherein said primary cabinet 19 can be eliminated by placing all the components also underground, inside the underground tank container 20, allowing for an access on the ground surface.

3. The flow battery according to claim 1, wherein said underground tank container is placed at a certain depth where the temperature range is stable at a suitable level,

4. The flow battery according to claim 1, wherein the secondary heat exchanger can be of tubular shape or other cross sectional shape, is composed of relatively low-cost plastic material such as Polypropylene or Polyethylene, and wherein said secondary heat exchanger, of tubular shape or other cross sectional shape, is in directed contact with the ground, obtaining the best heat transfer maximizing the efficiency.

5. The flow battery according to claim 1 wherein the primary heat exchanger, of tubular shape or else, may be made of low-cost plastic material such as an example Polypropylene or Polyethylene, and is placed inside both the electrolyte tanks in direct contact with the electrolyte, obtaining the best heat transfer maximizing efficiency.

6. The flow battery according to claim 1 wherein a coolant pump in connected to one side of the primary heat exchanger, of tubular shape or other cross sectional shape, while the other side of the pump is connected to the secondary heat exchanger, of tubular shape or other cross sectional shape, wherein the other sides of both primary and secondary heat exchanger are reciprocally connected to each other creating a single circuit.

7. The flow battery according to claim 1 wherein a glycol ethylene or other anti freezing compound solution is used inside the heat exchanger circuit.

8. The flow battery according to claim 1 wherein the heat produced by the reactions is dissipated in the ground by means of the heat exchanger circuit.

9. The flow battery according to claim 1 wherein the size is more compact than a conventional one, whereas the tanks that are placed underground, are also protected by potential damage derived by external impacts.

10. The flow battery according to claim 1 wherein the underground tank container 20 has an additional function as a spillage containment vessel.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

[0024] Further characteristics and advantages of the invention will become better apparent from the description of a preferred but not exclusive embodiment of the flow battery according to the invention, illustrated by way of non limiting example in the accompanying drawings, wherein:

[0025] FIG. 1 is a schematic view showing a conventional vanadium flow battery;

[0026] FIG. 2 is a schematic view of a flow battery module according to the state of the art;

[0027] FIG. 3 is a schematic view of a vanadium flow battery according to the present invention;

[0028] FIG. 4 is a diagram showing an example of geothermal temperature throughout the year at different depths.

DESCRIPTION OF EMBODIMENTS

[0029] As shown in FIG. 3, the objective of the present invention is to provide a vanadium redox flow battery module, having an innovative shape, which includes: at least one stack 17, at least one negative electrolyte tank 3, at least one positive electrolyte tank 4, at least two pumps 5 and 6, a primary cabinet 19, an underground container 20 for the tanks 3 and 4, the container 20 having a thermal insulation 18 between the container 20 and the tanks 3 and 4, at least one secondary heat exchanger 21, at least one primary heat exchanger 22, at least one coolant pump 23, wherein the container 20 is buried below ground level, while the primary cabinet 19 is to remain above ground level. The underground tank container 20 has an additional function also of acting as a spillage containment vessel.

[0030] The underground container 20 will be buried for example at 2 meters below ground level in order to capture the geothermal energy to keep the electrolyte temperature within the safe range as described in FIG. 4, minimizing the power consumption of the thermal management system. Meanwhile, in the present invention, the overall efficiency and reliability are increased due to the geothermal temperature stability. At 2 meters below ground level, ground temperature remains within the ideal range for the stability of vanadium flow batteries protecting the Battery Module from wide temperature fluctuations typical of an installation at surface level.

[0031] A further objective of the present invention is providing a flow battery that has small size, is relatively simple to put in operations and is safe to use.

[0032] FIG. 4 depicts in general terms a diagram showing an example of ground temperature versus the day of the year for different depths. The thermal excursion, e.g. at 2 meters, is stable in the range comprised between 6 degrees Celsius in the cool season and 13 degrees Celsius in the warm season.

[0033] In the flow battery Module according to the present invention, the underground container 20 will be buried for example at 2 meters below ground level where the ground temperature excursion is more stable than the external environment such as the one described in FIG. 4, eliminating the peaks of temperature which require an energy consumption for the thermal conditioning.

[0034] In the flow battery module according to the present invention, the thermal insulation 18 respectively between the underground tanks container 20 and the two tanks 3 and 4, will keep the electrolyte tanks thermally insulated.

[0035] In the flow battery module according to the present invention, the secondary tubular heat exchanger 21 is placed all around the underground tanks container 20. The secondary tubular heat exchanger 21 may be made of low-cost plastic material such as Polypropylene or Polyethylene, and the secondary tubular heat exchanger is in direct contact with the ground, obtaining close to the best heat transfer and attempts to maximize efficiency.

[0036] In the flow battery module according to the present invention, the primary tubular heat exchanger 22 is placed inside both electrolyte tanks 3 and 4, in direct contact with the electrolyte. By a coolant pump 23, one side of the primary tubular heat exchanger is connected to one side of the secondary tubular heat exchanger 21, wherein the other sides of both the primary heat exchanger 22 and the secondary tubular heat exchanger 21 are reciprocally connected creating a single circuit. A glycol ethylene solution fills the inside of the heat exchanger circuit.

[0037] The flow battery module according to the present invention, in the case of a harsh climate, by means of the geothermal temperature transferred to the underground tanks container 20 will remain within an ideal temperature range between +5 degrees Celsius and +13 degrees Celsius.

[0038] The flow battery module according to the present invention, in case of a hot climate, will transfer heat from the underground tanks container 20 to the ground and remain within the ideal temperature range, as the heat produced by the reactions is dissipated by the ground by means of the heat exchanger circuit.

[0039] In the flow battery Module of the present invention, an additional advantage is constituted by the fact that the size is more compact than the conventional ones, wherein the tanks placed underground are also protected by potential damage derived by external hits or shots.

[0040] In the flow battery module of the present invention, an additional advantage is constituted by the fact that the underground tanks container 20 has an additional function acting as a spillage containment vessel.

[0041] Meanwhile, in the present invention, the overall efficiency and the reliability are increased by means of the geothermal temperature stability, which will remain within an ideal range for the safe storage of the electrolyte, minimizing the energy consumption of the thermal management device.

[0042] Where technical features mentioned in any claim are followed by reference signs, those reference signs have been included for the sole purpose of increasing the intelligibility of the claims and accordingly such reference signs do not have any limiting effect on the interpretation of each element identified by way of example by such reference signs. Although the present invention has been described with reference to the preferred embodiments thereof, it is apparent to those skilled in the art that a variety of modifications and changes may be made without departing from the scope of the present invention which is intended to be defined by the appended claims.