Claims:We Claim;
1. A energy storage unit module (100) comprising of:
a casing (103) for placing plurality of energy storage unit inside it;
at least an end cover (102) for covering securely placed said energy storage unit in said casing (103);
said at least an end cover (102) having plurality of openings; opening A (111) and opening B (112) where said opening B (112) includes a pressure relief valve assembly (113); and
said pressure relief valve assembly (113) is detachably attached to said at least an end cover (102) of said energy storage unit module (100).
2. The energy storage unit module (100) as claimed in claim 1, wherein said at least an end cover (102) includes a U shaped profile (109), where a groove (110) of said U shaped profile (109) includes said opening A (111).
3. The energy storage unit module (100) as claimed in claim 1, wherein said opening A (111) locates a connector (100b) to connect said energy storage unit with a battery management inside energy storage module (100).
4. The energy storage unit module (100) as claimed in claim 1, wherein said pressure relief valve assembly (113) has a threaded portion (204d) which conforms with a counter threaded portion in said opening B (112) of said at least an end cover (102).
5. The energy storage unit module (100) as claimed in claim 1, wherein said at least an end cover (112) is detachably attached with said casing (101) with fasteners (100a).
6. A pressure relief valve assembly (113) for an energy storage unit module (100), said pressure relief valve cap assembly (113) comprising;
a relief valve cap (201) for covering upper side of said pressure relief valve assembly;
a relief valve housing (204); where said relief valve housing (205) is covered by said relief valve cap (201) from upper side of said pressure relief valve assembly (113);
a relief valve stem (205) housed inside said relief valve housing (204)
a relief valve elastic member (203) supported on said relief valve stem (205);
a relief valve nut (202) compresses said relief valve elastic member inside said relief valve housing (204)
said relief valve stem (205) housed inside said relief valve housing (204) shifts in outward direction along with said compressed relief valve elastic member (203) to form a passage for venting out excess internal pressure (shown by dotted arrow), when said internal pressure exceeds threshold pressure inside said energy storage unit module (100).
7. The pressure relief valve assembly (113) as claimed in claim 6, wherein said relief valve housing (204) has a lower end (204b), where said relief valve stem (205) has a funnel type profile (205a) which is seated on said lower end (204b) of said relief valve housing (204), when said internal pressure is lower than said threshold pressure.
8. The pressure relief valve assembly (113) as claimed in claim 7, wherein said lower end (204b) of said relief valve housing (204) has an opening (208), through which said excess internal pressure is channelized inside said pressure relief valve assembly (113), when a relief valve stem (205) of said pressure valve assembly (113) shifts in outward direction along with a relief valve elastic member (203) of said pressure valve assembly (113), when said internal pressure exceeds threshold pressure inside said energy storage unit module (100).
9. The pressure relief valve assembly (113) as claimed in claim 6, wherein said relief valve stem (205) has an outer diameter which is substantially equal to an inner diameter of said relief valve elastic member (203).
10. The pressure relief valve assembly (113) as claimed in claim 6, wherein said relief valve cap (201) has one or more perforations (206) to vent out excess internal pressure out of said energy storage unit module (100).
11. The pressure relief valve assembly (113) as claimed in claim 6, wherein said relief valve elastic member (203) has a length L which is substantially greater than a length L1 of said relief valve stem (205)
12. The pressure relief valve assembly (113) as claimed in claim 11, where said length L is in predetermined range of 40-45mm.
13. The pressure relief valve assembly (113) as claimed in claim 12, where said length L1 is in predetermined range of 25-30mm.
14. The pressure relief valve assembly (113) as claimed in claim 6, wherein said relief valve housing (204) has an upper end (204a), where said upper end (204a) has a threaded portion (204c) inside said relief valve housing (204) and said relief valve nut (202) having a threaded portion is detachably attached with said threaded portion (204a) present inside said relief valve housing (204) on said upper end (204a).
15. The pressure relief valve assembly (113) as claimed in claim 6, wherein said relief valve housing (204) has a lower end (204b) having threaded portion (204d) which is counter threaded and fastened with an opening B (112) present on at least an end cover (102) of said energy storage unit module (100).
16. The pressure relief valve assembly (113) as claimed in claim 5, wherein said relief valve housing has a collar type structure (207) having plurality of flat portions (207a, 207b).
17. A method for venting out excess internal pressure from an energy storage unite module through pressure relief valve, comprising;
placing a pressure relief valve assembly having relief valve cap, relief valve nut, relief valve elastic member, relief valve stem and relief valve housing in an energy storage unit module;
compressing a relief valve elastic member with said relief valve nut;
seating of relief valve stem in said relief valve housing, when an internal pressure generated inside said energy storage unit module is lower than threshold pressure;
lift movement of relief valve stem in outward direction along with compressed said relief valve elastic member, when an internal pressure generated inside said energy storage unit module exceeds threshold pressure; resulting in venting out of excess internal pressure;
channelizing of excess internal pressure in said relief valve housing of said pressure relief valve assembly; and
venting out of said excess internal pressure from said energy storage unit module through said relief valve nut and said relief valve cap of said pressure valve assembly. , Description:TECHNICAL FIELD
[0001] The present subject matter relates to an energy storage unit module. More particularly, the present subject matter relates to pressure venting from the energy storage unit module.
BACKGROUND
[0002] Typically, rechargeable energy storage units can be charged or discharged unlike primary energy storage units which are not capable of getting recharged. Generally, the low capacity energy storage unit where only one energy storage unit cell is packaged into a pack shape may be used as the power source for the various compact and portable electronic devices like the mobile phones etc. In case of high capacity energy storage unit, in which several numbers of energy storage units are connected in series or parallel, the high capacity energy storage unit may be used for powered devices e.g. power banks, laptops or driving motors such as electric scooters, hybrid vehicle etc.
[0003] The energy storage unit is proposed as a clean, efficient and environmentally responsible power source for powered devices like electric vehicles and various other applications. Typically, conventional energy storage unit module includes a plurality of energy storage unit cells arranged in a stacked configuration and also same is in electrical communication with an electrical device. Further, each of the energy storage unit cells includes cathode and anode terminals where the terminals are electrically connected in a combination of series & parallel configuration in order to maximize the voltage output & running time of the energy storage unit module. In certain designs, an energy storage unit cover has to be disposed over the stack of the energy storage unit cells to isolate and protect the anode and cathode terminals of each of the cells.
BRIEF DESCRIPTION OF THE DRAWINGS

[0004] The detailed description is described with reference to the accompanying figures. The same numbers are used throughout the drawings to reference features and components.
[0005] Fig. 1 is an assembled view of energy storage unit module as per one embodiment of the present invention.
[0006] Fig. 1a is an assembled view of casing as per one embodiment of the present invention.
[0007] Fig. 1b is a perspective view of a front end cover as per one embodiment of the present invention.
[0008] Fig. 1c is a sectional view of the energy storage unit module with a pressure relief valve as per one embodiment of the present invention.
[0009] Fig. 2 is an exploded view of pressure relief valve as per one embodiment of the present invention.
[00010] Fig. 2a is a sectional view of pressure relief valve as per one embodiment of the present invention.
[00011] Fig. 2b is a perspective view of pressure relief valve with inner and outer threading as per one embodiment of the present invention.
[00012] Fig. 2c is an assembled view of pressure relief valve with one or more perforations as per one embodiment of the present invention.
DETAILED DESCRIPTION
[00013] In recent times, for environmental protection there has been a strong demand for the reduction of the amount of carbon dioxide emission. Especially, in automobile industry, expectations have been rising towards the reduction of carbon dioxide emission by introducing electric vehicle or a hybrid vehicle. As a result, the energy storage unit industry is continually expanding to meet the increasing energy needs of the portable equipment, transportation and communication markets.
[00014] Generally, energy storage units are classified into primary and secondary energy storage units, where the primary energy storage units are also referred as the disposable energy storage units and mostly intended to be used until exhausted after which the energy storage unit is simply replaced by one or more energy storage units. Secondary energy storage units commonly referred as rechargeable energy storage units that can be repeatedly recharged and reused, thus are economical in the long run, environmentally friendly as compared to disposable energy storage units.
[00015] While rechargeable energy storage units offer many advantages over primary energy storage units but also has some drawbacks which are based on the chemistry of the energy storage unit used. The chemistry of the secondary cell is less stable as compared to the primary cell. Further, due to these relatively unstable chemistries, special handling of the secondary cell is often required during manufacture.
[00016] The secondary energy storage unit is divided into two parts namely, lithium ion energy storage unit and lead acid energy storage unit. The lead acid energy storage units are the most common large capacity rechargeable energy storage units. The lead acid energy storage units are built with a number of individual cells containing layers of lead alloy plates immersed in an electrolyte solution, typically made up of sulphuric acid and water. Pure lead (Pb) is too soft and would not support itself, so small quantities of other metals are added to get the mechanical strength and improve electrical properties. The most common additives are antimony (Sb), calcium (Ca), tin (Sn) and selenium (Se). When the sulphuric acid comes into contact with the lead plate, a chemical reaction occurs and energy is produced. The lead acid energy storage unit works well at cold temperatures and is superior to lithium ion energy storage unit, when operating in sub-zero conditions
[00017] The lithium ion energy storage unit is typically configured as a secondary energy storage unit (rechargeable energy storage unit), which mainly depends on lithium ions (Li+) moving between a positive electrode and a negative electrode to work. During charging and discharging, Li+ is embedded and travels between two electrodes; Li+ is withdrawn from the positive electrode, and the electrolyte is embedded in the negative electrode, and the negative electrode is in a lithium-rich state. When charging, the lithium ion energy storage unit generally uses a material containing lithium as an electrode, which is representative of modern high-performance energy storage units.
[00018] Further, the Li ion energy storage units are produced with a number of variations and the most popular Li ion energy storage units, having the highest energy density, use a cobalt or nickel cobalt oxide anode. These energy storage units also have the disadvantage like when overheated, they tend to create their own internal supply of oxygen. More particularly oxygen is released from the oxide material of the anode at high temperature, which occurs due to many reasons like internal short circuit, overcharging, or any other causes. Since both oxygen and fuel are both internally available to the cells, a fire can start within a single cell, leading to safety risks.
[00019] Moreover, the secondary energy storage unit such as lithium ion energy storage units tend to be more vulnerable to the thermal runaway than lead acid energy storage units. When the temperature within module is increased above the threshold temperature because of the abnormality in the cells or operation within the module, it causes gas particles as generated inside the module to move faster. As the gas particles move faster, it increases the number of collisions of gas particles inside the module. Therefore, this leads to excess internal pressure generation within the module. If this excess internal pressure is not vented out or released from the module timely, it increases the safety risk from a potential explosion or fire arising out of a thermal runaway of the system. The main reasons for thermal runaway are shorting within the cell, improper use of the cell, physical abuse, manufacturing defects or exposing the cell to excessive external temperatures.
[00020] Thermal runaway is an important issue because a single event of thermal runaway can cause serious physical harm\damage and in some case, it can cause harm to the human body or loss of life. When the energy storage unit is in thermal runaway condition, the energy storage unit generally emits a large amount of a smoke, a jet of burning liquid electrolyte and significant heat, which results into the burning and destruction of the surrounding components nearby to the energy storage unit. Also, if the energy storage unit module is having a stack of the cells, a single thermal runaway event will instantly cause thermal runaway of the multiple cells, hence, potentially causing extensive damage to the stack of the cells and its surrounding components. Further, the flame generated due to thermal runaway condition, also contributes in the increase of effect of property damage if the initial flame is not instantly extinguished, irrespective of the energy device consisting of single cell or the multiple cell.
[00021] During a thermal runaway in a laptop or electric vehicle, the thermal runaway without any human presence can cause not only damage to the laptop but also, at least some damage to the surrounding near to the laptop like as home, offices, cars etc.. Furthermore, worst situation can occur if the laptop energy storage unit is mounted on the board of aircraft, the resulting smoke due to thermal runaway can cause a fatal crash landing or emergency landing in more demanding situations. Similarly, the thermal runaway of one or more energy storage units in the energy storage unit module of the hybrid or electric vehicle not only damages the vehicle but also can cause accident and damage to the environments surrounding the components of the vehicles. Hence, it is apparent from the above discussed paragraphs that venting out of the excess internal pressure from a sealed casing is important to lower down risk of thermal runaway in the energy storage unit module.
[00022] Generally, a sealed energy storage unit’s module, having ends made up of plastic, are commercially available or commercially used. Further, the abnormality inside the cell of energy storage unit or operation of cells on high temperature, leads to generation of gas inside the module. The high temperature inside the module leads to movement of the gas particles inside the module and this leads to increase in internal pressure inside the module. As the internal pressure increases inside the module, the ends of the module made up of plastic melt and thus the excess internal pressure, as generated inside the module, is vent out. This leads to another problem like user has to change the complete module of the energy storage unit. This increases the overall cost of energy storage unit module and also is cumbersome to the user. Hence, to overcome this problem, there is a need of pressure relief valve in the energy storage unit module to release/vent out the excess internal pressure as generated inside the energy storage unit module, to avoid any kind of safety hazards.
[00023] Further, in known art, a sealed energy storage module configured to accommodate energy storage unit is known. When an abnormality like thermal runaway occurs because of thermal failure, mechanical failure, internal/external short circuiting, in the module of energy storage unit, gas is generated in the sealed module and this leads to rise in the internal pressure within the sealed module. Therefore, when the internal pressure exceeds the threshold pressure, the pressure relief valve located in the sealed module breaks to vent out the excess internal pressure outside the sealed module. However, this raises another problem like replacement of the pressure relief valve thereby leading to replacement of the components which is not cost effective and cumbersome for the user to replace the entire energy storage unit.
[00024] I In known art, to prevent thermal runaway, different types of mechanism are used namely, energy storage unit management system to control charge mechanism to avoid high temperatures, step charging, pulse charging or adding cooling systems like fins etc., which require additional manual intervention in case of failure like failure in BMS (Energy storage unit Management System) circuit etc.
[00025] Hence, there exists a challenge of designing an efficient energy storage unit module without any major change in design and manufacturing set-up of the vehicle.
[00026] Therefore, there is a need to have an improved energy storage unit module which overcomes all of the above problems and other problems of known art.
[00027] The present invention provides a solution to the above problems while meeting the requirements of minimum modifications in a powered device at low cost with ease of manufacturing etc.
[00028] With the above objectives in view, the present invention relates to the energy storage unit module and more particularly to an improved configuration of energy storage unit module where a one way pressure relief valve assembly is detachably attached with the energy storage unit module to vent out excess internal pressure generated inside the energy storage unit module arising out of the failure like thermal runaway, thereby, making it cost effective, increasing ease of assembly and also, safe for the riders.
[00029] As per one aspect of the present invention, the energy storage unit module comprises of a casing, a front end cover and a rear end cover. The end covers are detachably attached to the casing of the module with various attachment means like fasteners. As per one aspect of the present invention, the front end has grooves with opening, for example, opening A. The opening A accommodates a connector which connects the energy storage unit with battery management system inside the module. A one way pressure relief valve assembly (referred here as pressure relief valve assembly) is disposed in an opening B located on the front end cover of the module. This pressure relief valve assembly releases the high internal pressure generated inside the module, thereby ensuring safety of users.
[00030] As per one aspect of the present invention, the pressure relief valve assembly comprises of a relief valve cap, a relief valve nut, a relief valve elastic member e.g. an elastic member, relief valve housing and a relief valve stem. The relief valve stem is housed inside the relief valve housing. The relief valve housing has perforation at lower end to channelize the excess internal pressure generated inside the module because of the generation of gasses inside the module. Further, as per one aspect of the present invention, the relief valve elastic member is supported on the relief valve stem and the relief valve preloading nut is fixed on the relief valve elastic member of the pressure relief valve assembly. The pressure relief valve assembly is closed or covered by a relief valve cap from upper side of the pressure relief valve assembly. The relief valve cap also has one or more perforations to vent out the excess internal pressure as channelized inside the pressure relief valve by the relief valve housing. When the internal pressure increases inside the energy storage module because of the operations/abnormality inside the energy storage unit module, the lower end opening of the relief valve housing channelizes the excess internal pressure inside the pressure relief valve assembly. As the relief valve stem shifts/lifted in outward direction because of the increased internal pressure in the module, this leads to compression of the relief valve elastic member. This outward shifting of the relief valve stem creates a passage to channelize excess internal pressure inside the pressure relief valve assembly. Also, when the pressure level goes down below the threshold internal pressure value, the relief valve elastic member helps the relief valve stem to regain its original position inside the pressure relief assembly. The relief valve nut, which is a preloading nut, helps in working of the relief valve elastic member of the pressure relief valve assembly at different value of the internal pressure generated inside the module. This ensures the timely release of pressure generated inside the module, which ultimately protects the module from thermal runaway. The relief valve elastic member tension in the relief elastic member wall ensures support to the relief valve stem and helps the relief valve stem to maintain its original position
[00031] As per one aspect of the present invention, the relief valve housing has a collar type structure having plurality of flat profiles on both sides of the collar. This relief valve housing is detachably attached to the opening B located in the rear cover of the module and thus protects the opening B from dust, contamination etc.
[00032] It is contemplated that the concepts of the present invention may be applied to any of the two wheeled, three wheeled, four wheeled type vehicle and any other devices which requires energy storage unit module to operate.
[00033] Various other features of the invention are described in detail below with reference to the accompanying drawings. In the drawings, like reference numbers generally indicate identical, functionally similar, and/or structurally similar elements. The drawing in which an element first appears is indicated by the leftmost digit(s) in the corresponding reference number. With reference to the accompanying drawings, wherein the same reference numerals will be used to identify the same or similar elements throughout the several views. Further, the present subject matter can be implemented on both the terminals of cylindrical cells.
[00034] Fig. 1 is an assembled view of an energy storage unit module (100). As per one embodiment of the present invention, the energy storage unit module (100) comprises of a casing (101), a front end cover (102) and a rear end cover (not shown). The energy storage unit module is made of metal. Further, the casing (101) includes plurality of walls like a pair of side walls (103, 104), an upper wall (105) and a bottom wall (106) which also act as the base panel to locate plurality of energy storage unit inside the energy storage unit module (100) (as shown in fig. 1a). Further, as per one embodiment of the present invention, the front end cover (102) is detachably attached to the casing (101) of the energy storage unit module (100) with various attachment means like fasteners (100a). The front end cover (102) has plurality of openings (102a) (as shown in fig. 1b) which compliments with a plurality of openings (107) present on the casing (101) (as shown in fig. 1a) of the energy storage unit module (100).
[00035] Further, as per one embodiment of the present invention, the front end cover (102) has a plurality of cut out portions (108a, 108b and 108c), where the cut out portions provide ease of accessibility of the fasteners in the energy storage unit module. Further, as per one embodiment of the invention, the front end cover (102) has a U shaped profile (109), where groove (110) of the U shaped profile includes an opening, i.e., opening A (111) for accommodating a connector (100b) to connect the energy storage unit with battery management system within the module with battery management system (not shown). Further, as per one embodiment of the present invention, the front end cover has an opening B (112) (as shown in fig. 1b) at an extreme end to configure a pressure relief valve assembly (113) in the energy storage unit module (100). In another implementation, the pressure relief valve assembly can be placed detachably on any wall of the energy storage unit module. The pressure relief valve assembly (113) is detachably attached to the opening B (112) of the front end cover with different attachment means e.g. , the pressure relief valve assembly (113) has a threaded portion (204d) (as shown in fig. 1c) which conforms with counter threaded portion in opening B of the front end cover. Furthermore, in another implementation, the pressure relief valve assembly can be implemented in the energy storage unit module where the end covers are made up of plastic. This ensures that the excess internal pressure is vented out by the pressure relief valve assembly, eliminating the need of replacing the components.
[00036] Fig. 2 is an exploded view of the pressure relief valve assembly as per one embodiment of the present invention. The pressure relief valve assembly (113) includes a relief valve cap (201), a relief valve nut (202), a relief valve elastic member (203); a relief valve housing (204) and a relief valve stem (205). The relief valve stem (205) is housed inside the relief valve housing (204). A wire mesh (not shown) is placed between the relief valve cap and the relief valve nut to protect the pressure relief valve assembly from the dust particles. Further, as per one embodiment of the present invention, the relief valve stem (205) has funnel type profile (205a) which is seated on lower end (204b) of the relief valve housing (204) (as shown in fig. 2a) to avoid leakage inside the pressure relief valve assembly (113), that is, no atmospheric air is transferred to the energy storage unit module through the relief stem valve, when internal pressure is lower than the threshold pressure inside the module. The relief valve housing (204) has a threaded portion (204d) on the lower end (204b) (as shown in fig. 2b) which is counter threaded and fastened with a threaded portion (not shown) present in the opening B of the front end cover (112).This ensures the attachment of the pressure relief valve to the front end cover is with minimum number of components. The relief valve housing (204) has opening (208) (as shown in fig. 2c) at lower end to channelize the increased internal pressure generated inside the casing because of the operations inside the casing.
[00037] Further, as per one embodiment of the present invention, the relief valve nut (202) is threaded inside threaded portion (204c) (as shown in fig. 2b) of the relief valve housing (204) on an upper end (204a) of the relief valve housing (204) (as shown in fig. 2a). The relief valve nut is a preloading nut which helps in working of the relief valve elastic member of the pressure relief valve assembly at different value of the internal pressure. , generated inside the energy storage unit module. For example, the preloading nut is tightened by a spanner and supported on the relief valve elastic member to resist the pressure build up to 1bar inside the casing. This means that the relief valve elastic member is compressed by the preloading nut to tolerate the 1 bar pressure build up in the module. When the pressure exceeds beyond 1 bar, the relief valve stem shifts/lifted in outward direction along with the relief valve elastic member by overcoming the elastic member compressive force. Thus, the excess internal pressure is channelized into the relief valve housing (204) and is finally vented out by the one or more perforations (206) present on the relief valve cap respectively. Further, when the internal pressure drops the level below the threshold pressure that is 1bar, the relief valve elastic member (203) comes to its original position along with the relief valve stem (205), as now there is no excess pressure generated and hence, force applied to shift the relief valve stem (205) is inadequate to enable outward movement of the relief valve stem (205) along with the relief valve elastic member (203). Thus, the relief valve stem (205) and the relief valve elastic member (203) come to the original position in the pressure relief valve assembly (113). The elastic member tension in the elastic member ensures support to the relief stem valve (205) and helps the relief stem valve (205) to maintain its position. This ensures the timely release of excess pressure generated inside the casing, which protects the energy storage unit module from thermal runaway.
[00038] Further, as per one embodiment of the present invention, the relief valve elastic member (203) is supported on the relief valve stem (205) (as shown in fig. 2a) as outer diameter of relief valve stem is substantially equally to inner diameter of the relief valve elastic member. The relief valve stem is made up of metal like aluminum. The pressure relief valve assembly (113) is closed or covered by a relief valve cap (201) from upper side of the pressure relief valve assembly. The relief valve cap (201) also has one or more perforations (206) (as shown in fig. 2c) to vent out the excess internal pressure as channelized inside the pressure relief valve assembly (113) by the relief valve housing (204). When the internal pressure increases inside the energy storage unit module because of the operations/abnormality inside the energy storage unit module, the lower end opening (208) of the relief valve housing (204) channelizes the excess pressure inside the pressure relief valve assembly (113). As the relief valve stem (205) shifts/lifted in outward direction because of the increased internal pressure in the module, it leads to the further compression of the relief valve elastic member (203). This outward shifting/lifting of the relief valve stem (205) creates a passage to channelize excess internal pressure inside the pressure relief valve assembly (113). Therefore, the pressure as generated inside the module is channelized inside the pressure relief valve assembly (113) through the lower end of the relief valve housing (204) and is vented out through passage formed in the relief valve nut (202) and the one or more perforations/openings (206) present on the relief valve cap (201) (venting out of internal pressure shown by dotted arrow) (as shown in fig. 2a). Further, length (L) of the relief valve elastic member is more than the length (L1) of the relief valve stem (205) (as shown in fig. 2), therefore, the relief valve stem (205) does not create hindrance/obstacle in a passage formed in preloading nut (202) and the relief valve cap (201) for venting out the excess internal pressure. The length L of the relief valve elastic member (203) is in predetermined range of 40-45mm. More than or less than the predetermined range adversely affects the compression of the relief valve elastic member 203. The length L1 of the relief valve stem (205) in in predetermined range of 25-30mm. More length than the predetermined length of the relief valve stem (205) acts as the obstruction in the passage of venting out of internal pressure generated. Less length than the predetermined length is inadequate to support the relief valve elastic member (203), thus impact the working of pressure relief valve assembly. Also, when the pressure level goes down below the threshold internal pressure value, the elastic member (203) helps the relief valve stem (205) to regain its original position inside the pressure relief assembly 113. For example, when the internal pressure as generated inside the casing of the energy storage unit module is more than 1bar, then the pressure relief valve (113) vents out the excess pressure from the one or more perforations present on the relief valve cap 206since any excess pressure inside the module is detrimental for the working of the energy storage unit and also leads to thermal runaway which ultimately increases the safety risk for the user.
[00039] Further, as per one embodiment of the present invention, the relief valve housing (204) has a collar type structure (207) having plurality of flat profiles (207a, 207b) (as shown in fig. 2c) on both sides of the collar. This ensures ease of tool accessibility while assembling the pressure relief valve assembly with the energy storage unit module.
[00040] The invention helps in overcoming the problems while ensuring the safety of the surrounding components of the energy storage unit module.
[00041] Advantageously, the embodiments of the present invention, describes the potential modifications in the assembly of the energy storage unit module which includes a one way pressure relief valve with a preloading nut, which releases excess internal pressure as generated inside the casing of the energy storage unit module. The present invention facilitates the simple and easy releasing of excess internal pressure as accumulated in the energy storage unit module while efficiently increasing the ease of accessibility and safety of the surrounding components of the energy storage unit module.
[00042] Many other improvements and modifications like using different elastic means having stiffness may be incorporated herein without deviating from the scope of the invention.
List of reference symbol:
Fig. 1:
100: Energy storage unit module
100a: fasteners
100b: connector
101: casing
113: pressure relief valve assembly
102: Front End Cover
Fig. 1a
103, 104: Pair of Side Walls
105: Upper Wall
107: openings
106: Bottom Wall
Fig. 1b
108a, 108b, 108c: plurality of cutout portions
111: opening A
102a: plurality of openings
110: groove
109: U shaped profile
Fig: 2
201: relief valve cap
202: relief valve nut
203: relief valve elastic member
204: relief valve housing
205: relief valve stem
Fig. 2a
204a: upper end of the relief valve housing
204b: lower end of the relief valve housing
205a: funnel type profile
Fig. 2b
204c: threaded portion on the outer surface of the relief valve housing
204d: threaded portion on the inner surface of the relief valve housing
207: collar type structure
207a: flat profiles
Fig. 2c:
206: one or more Perforations.