Patent Application
20240088482
The present disclosure relates generally to a thermal management control system for lithium-ion battery storage.
Thermal runaway in a battery system often begins in a single cell. Thermal runaway may be characterized by primary effects including vapor combustion, over-pressurization, explosion of the cell contents, and generation of heat and/or flames. These effects may cascade from the initial cell(s) where thermal runaway originates to other adjacent cells, leading to propagation of thermal runaway throughout a battery system. Secondary effects of non-contained thermal runaway may include harm to people, environmental damage, and/or destruction of property. Cooling systems are used to control thermal runaway.
The disclosure includes a battery system. The battery system includes a battery cooling system, the battery cooling system including a battery chiller, battery pods in fluid connection with the battery chiller, and at least one chiller pump, the at least one chiller pump in fluid communication with the battery chiller and the battery pods. The battery system also includes a heat exchanger, the heat exchanger in fluid communication with the battery cooling system and an inverter loop. In addition the battery system includes the inverter loop including active front end rectifiers (AFE) and LCL filters (LCL), an inverter pump in communication with the AFE and the LCL, and a temperature sensing control valve adapted to stop or start flow of an inverter loop cooling fluid from reaching the heat exchanger. Further, the battery system includes a controller, the controller in electrical communication with the chiller pumps and adapted to control the temperature of a fluid coolant or control the rate of pumping of the chiller pumps, wherein the fluid coolant is adapted to be cooled by the chiller and pass through the battery pods.
The present disclosure is best understood from the following detailed description when read with the accompanying figures. It is emphasized that, in accordance with the standard practice in the industry, various features are not drawn to scale. In fact, the dimensions of the various features may be arbitrarily increased or reduced for clarity of discussion.
It is to be understood that the following disclosure provides many different embodiments, or examples, for implementing different features of various embodiments. Specific examples of components and arrangements are described below to simplify the present disclosure. These are, of course, merely examples and are not intended to be limiting. In addition, the present disclosure may repeat reference numerals and/or letters in the various examples. This repetition is for the purpose of simplicity and clarity and does not in itself dictate a relationship between the various embodiments and/or configurations discussed.
In chiller 20, heat in the fluid coolant is exchanged with a chiller cooling fluid. The chiller cooling fluid is most often glycol although other chiller cooling fluids such as water may be used. The cooled fluid coolant that exits chiller 20 is then circulated to battery pods 30. Battery pods 30 generate heat from charging or discharging. As described above in the Background Section, overheated battery pods are problematic and cooling battery pods 30 leads to better performance and can avoid or reduce catastrophic thermal runaway.
As one of ordinary skill in the art would recognize with the benefit of this disclosure, battery pods 30 may be arranged in a variety of configurations. In mobile battery structures such as shown in
In certain embodiments, fluid coolant management devices may be used in battery cooling system 10, such as air separator tank 50, where entrained air within the fluid coolant may be expelled, volume tank 60, where a reservoir of fluid coolant is kept, and expansion tank 70, where expansion of fluid coolant due to temperature rise with battery cooling system 10 is addressed. As one of ordinary skill in the art with the benefit of this disclosure will recognize, various check valves, isolator valves, pressure and temperature sensors, and discharge valves may be used in battery cooling system 10.
Heat exchanger 40, when in operation, may use a portion of the fluid coolant to absorb heat from an inverter loop cooling fluid.
With attention to
Inverter loop 200 may also include temperature sensing control valve 240. In certain circumstances, such as when the batteries of battery pods 30 are not charging or discharging, the inverter components, such as AFE 216 and LCL 214 may not heat. In such cases, temperature sensing control valve 240 may close based on measurement of a low set point temperature and stop the flow of inverter loop cooling fluid from entering heat exchanger 40. When the inverter loop cooling fluid temperature rises above the low set point temperature, temperature sensing control valve 240 may open and allow inverter loop cooling fluid to be cooled in heat exchanger 40.
Inverter loop 200 may include other vessels, such as inverter loop air separator 250 and expansion tank 260.
Controller 300 controls the rate of cooling of battery pods 30 by controlling the temperature of the fluid coolant or by increasing the pump rate of the chiller pumps 22. As rate of battery power is correlated to battery pod temperature, the higher the rate of battery power, the lower the temperature of the fluid coolant of the pump rate of chiller pumps 22.
Often, battery cooling system 10 is within an enclosure 14. Enclosure 14 has an enclosure temperature and enclosure humidity resulting in an enclosure dew point. When fluid coolant cools to enclosure dew point or lower, water may condense on the outside of the battery cooling system 10 components. Electronics associated with battery cooling system 10 components, including controller 300, may be damaged by such condensate. In such cases, controller 300 may change the set point of fluid coolant temperature to above the dew point. In one such embodiment, a safety margin, such as a temperature between 1 and 10° C. may be chosen such that fluid coolant temperature remains at least the safety margin above the dew point temperature of the enclosure. In these embodiments, the controller adjusts the fluid coolant temperature to the working temperature of the battery cooling system, such as 50° C. or the dew point temperature (plus the safety margin), whichever is greater. Dew point temperature plus the safety margin may be calculated by the controller according to the following algorithm:
During startup of battery system 18, it may be desirable for controller 300 to override temperature shutdown alarms, as the temperature of battery cooling system 10 has not yet reached steady state. The startup period may range in some embodiments from 1 to 10 minutes. In the embodiment shown in
In certain embodiments, battery system 18, enclosure 14, battery cooling system 10 and inverter loop 200 may be mobile, such as placed on a trailer. In some embodiments, the trailer may be a gooseneck trailer. In yet other embodiments, portions of battery system 18, enclosure 14, and battery cooling system 10 may be physically separated from inverter loop 200, such as wherein chiller 20 may be on a remote portable skid or trailer.
The foregoing outlines features of several embodiments so that a person of ordinary skill in the art may better understand the aspects of the present disclosure. Such features may be replaced by any one of numerous equivalent alternatives, only some of which are disclosed herein. One of ordinary skill in the art should appreciate that they may readily use the present disclosure as a basis for designing or modifying other processes and structures for carrying out the same purposes and/or achieving the same advantages of the embodiments introduced herein. One of ordinary skill in the art should also realize that such equivalent constructions do not depart from the spirit and scope of the present disclosure and that they may make various changes, substitutions, and alterations herein without departing from the spirit and scope of the present disclosure.
This application is a nonprovisional application which claims priority from U.S. provisional application No. 63/405,267, filed Sep. 9, 2022, which is incorporated by reference herein in its entirety.
| Number | Date | Country | |
|---|---|---|---|
| 63405267 | Sep 2022 | US |
