The present invention relates to the vent plug of Lead Acid type battery which prevents the electrolyte leakage from the battery and ensures Leak Proof Battery for customer. The present invention also provides for a solution to electrolyte Leakage from the battery at certain angles from Vent Plugs.
BACKGROUND OF THE INVENTION:-
A lead acid battery includes: a positive plate including a positive electrode spine and a positive electrode active material; a negative plate including a negative electrode grid and a negative electrode active material; an electrode plate group including the positive electrode plate, the negative electrode plate, and a separator interposed between the positive electrode plate and the negative electrode plate; a battery container including a plurality of cell chambers each accommodating the electrode plate group and an electrolyte; a lid sealing an opening of the battery container and the vent plug. Electrical storage batteries, such as lead-acid batteries used for automotive purposes, include a container having a plurality of individual compartments, each of which house a cell composed of plates, electrolyte and associated connecting means. The battery container cover has an opening or filling well for each cell which is used to introduce electrolyte to the cell compartment, to inspect the electrolyte level during battery use and to add electrolyte or water as required. These filling wells also permit access for test probes which may be used for measuring the cell voltage level. Each filling well is provided with a cap or plug to prevent the loss of electrolyte. These plugs are provided with small vent holes or passageways for venting to atmosphere, gases which evolve during chemical reactions taking place in the cell. A certain amount of electrolyte normally escapes from the cell in the form of a mist or vapor entrained in the gases. A certain amount of electrolyte also normally escapes through the vent plugs as a result of splashing when the battery is subjected to rough use, such as in vehicles moving over rough terrain or in boats. Also, a certain amount of electrolyte normally will spill through the vent plugs as a result of the battery being tipped during transportation or storage of the battery itself or while the battery is installed, such as during the transportation of automobiles in an angular position on transit carriers. During service of a battery, the vent plugs must be frequently removed for inspection of the electrolyte level. Some batteries utilize individual vent plugs which must be removed and replaced separately. The removal and replacement of each individual plug is very time consuming as the removed plugs are quite easily misplaced or dropped causing further delay or

difficulty for an attendant servicing the battery.
US 3597280 discloses a multiple vent plug assembly is provided which includes a hollow body composed of a base, having peripheral walls, and a cover connected to the walls. A plurality of hollow vent plugs, which depend from the bottom of the base, open into separate chambers defined by lateral partitions depending upwardly from the base and connecting to the walls. Means are provided for permitting the egress of gases from the battery cells to atmosphere upward through the vent plugs into the chambers and from the chambers to atmosphere through the base, while sufficiently obstructing the passage of the egressing gases so that the inadvertent discharge of electrolyte from the cells is minimized. In a preferred embodiment, the venting means consist of vertical vent stacks which are provided as an integral part of some of the partitions. These vent stacks have openings at the top adjacent to the cover which communicates with two chambers. In another embodiment, circular skirts, which are coaxial extensions of the vent plugs inside the body, act as baffles. These skirts are provided with vertical slotted openings through which the egressing gases pass to maximize the separation of electrolyte from the gases.
US 3879227 discloses a vent plug for a storage battery wherein a porous diffuser is disposed in a hollow body member having a first chamber and adjacent a second compartment to pre-vent accumulations of and afford diffusion of cell gases after their egress from the battery. In one embodiment a plurality of partition means is provided in a hollow body member forming a gang type vent so as to permit the flow of gases to a single porous diffuser while at the same time retarding the flow of electrolyte. In the gang type vent, the floor of the hollow member is gabled and tubular members adjacent the cell vent openings are designed at an oblique angle so as to afford maximum drain back of escaped electrolyte. In an alternative embodiment, the diffuser is disposed in a chamber in a single, hollow body member and adjacent a second compartment with an outlet.
KR101220484B1 discloses a vent plug for a battery, the vent plug being detachable to discharge the internal gas of the battery, the vent plug being disposed above the vent plug, having a head space into which gas is introduced, and in a lateral direction. A head body having a gas discharge hole through which at least one outer periphery penetrates the head space and gas is discharged to the outside, and disposed inside

the head body, and filtering the gas discharged by being located inside the head space A filter, a head flange protruding around the lower outer periphery of the head body, the head flange fixedly supported while contacting the lower surface when the battery is inserted, protruding from the lower part of the head body, and in communication with the head space therein. An insertion body having a space and inserted when the battery is mounted, and the insertion It is disposed on the outer surface of the body, and includes a fastening screw is formed to be screwed to the storage battery.
US 4328290 discloses The improved vent plug is defined by a housing having a mounting portion adapted to be mounted in a battery cover opening, a vent chamber, an annular seat confronting the vent chamber, an inlet opening through the seat to the vent chamber, and an outlet opening through a portion of the housing spaced from the inlet, a resilient body in the chamber having a sealing portion adjacent the inlet, and a force transfer portion opposite the sealing portion, and means on the housing for applying a compressive force to the force transfer portion directed through the body to urge the sealing portion against the seat for releasably sealingly closing the inlet, the resilient body being compressed toward the force transfer portion as a result of a preselected elevated fluid pressure in the inlet to space the sealing portion from the seat and permit flow of the fluid through the vent chamber about the resilient body to the outlet and to permit the resilient body to have the sealing portion resealed to the seat upon dropping of the fluid pressure below the preselected fluid pressure.
The filling of battery cells with water with adequate electrolyte and to prevent accumulation of gases during the charging and discharging of a battery have always been a problem in the storage battery industry. Gang type multiple vent plug assemblies which afford some degree of quick access to the cells in a storage battery and venting of the cells are common in the industry. Generally, with the prior art multiple vent plug assemblies, an inversion or partial tipping of the battery during handling or transportation results in liquid electrolyte leaking out through the vent passageways. Also, condensate from the vaporous electrolyte venting to atmosphere tends to collect on the underside of the prior art multiple vent plug assemblies. This condensate can migrate to the top of the battery and result in an accumulation of corrosive acid thereon.

Lead Acid batteries are widely used as power source in many applications such as automotive, telecom, electric vehicles, uninterruptible power supply (UPS), traction etc. But the problems in lead Acid battery remain is that of electrolyte spillage, water loss, which is made of different components are used in vent plug assembly like Main body, rubber washer, threads, PP Disc, Baffle, locking in existing lead acid battery used for automotive 8s E Vehicle application. Due to the moving application leakage comes out on top of battery cover and contniuous leakage from vent plug results in cell level getting low which tends to plates overheating and harm the battery.
So, this invention involves the improvement of above constraints by using design 8s process changes in components of vent plug which helps out to resolve the current obstacles of use of flooded lead acid battery in this particular application.
OBJECT OF THE INVENTION:
The major role which prevents the electrolyte leakage from the battery is the
"VENT PLUG". Accordingly, So, this invention involves the improvement over the above constraints by changes in design & process of the vent plug which helps in overcoming the obstacles for the use of the flooded lead-acid batteries in stationary applications. This present invention relating to the vent plug of the lead-acid battery prevents the electrolyte leakage from the battery and ensures leak proof battery for the customer.
BRIEF DESCRIPTION OF DRAWINGS:
Fig.a. Isometric View of Vent Plug Fig.b. Top View of Vent Plug Fig.c. Front View of Vent Plug
DESCRIPTION
The present invention provides for a vent plug in accordance with the following disclosure and the drawings. The vent plug in accordance with the present invention comprises of a main body, washer, a thread, a Baffle, Gassing hole, a PP disc. The vent plug main body is being manufactured in accordance with the shape as disclosed in fig 1 having fitment with PP disc, baffle & with main body. The main body of the vent plug could be of standard grade preferably with PPCP Haldia M310 & IOCL 4100 MH grade. Vent plug washer fig. a part no. 3 made of EPDM rubber.

It is important that during molding of vent plugs main body part must be fitted with PP Disc within one minute time duration with press fit tool. This ensure that the molding while hardening gets engaged with the PP disc tightly to ensure leak proof vent plug. The vent plugs main body The internal diameter of the main body of the vent plug is 14.9 mm and will be fitted with the disc having a diameter of 14.8 mm. This happens due to the material shrinkage property (1.8- 2.5 %). The internal diameter of the vent plug contracts & makes an interference fit of 0.1 mm with the disc. Since the main body is coming out from the mold, it shrinks due to the temperature difference to that of the ambient temperature. But the shrinkage should be limited for a standard limit of 1.8 % - 2.5%. Since we are fixing the disc in a minute's time, the walls of the disc do not allow the material to shrink and so the diameter contracts less than 0.26 mm - 0.37 mm as per the standard shrinkage allowance and it maintains on 14.8 mm size, as required for this work, in fitting and avoids the leakage issues. If the disc fitting cycle time is more than the required one, then there is a risk of breaking or lack of proper fitting. This is due to the shrinkage rate which was tested and found as per the standard requirements. Accordingly the disc fitment cycle time is an important aspect of the invention since if more than one minute time is required, there is risk of breaking or improper fitment due to shrinkage rate which was tested & found as per standard requirements.
PP Disc: As mentioned in Figure. 1 (part 8), it represents PP disc. The general properties of PP disc are such as high melting point, porosity, and poor conductivity. These properties makes it more reliable and highly efficient in the vent plugs. It also works as a flame arrestor. The PP disc was optimized with the porosity fixed at 35-43%. It helps in the condensation process which in turn controls the water loss & slows down the leakage from the battery. During charging, evolution of gases will happen. So, around 5mm gap was designed to be present in between the disc & the fume passing hole for the purpose of condensation process of gases which later pass through the pores of the disc that acts as a reservoir for liquid droplets of electrolytes to come in directly. PP disc also helps in filtering the hydrogen gases to save our environment. Disc did not allow the dense gases to evaporate into the air easily. PP Disc also allows liquid

droplets to get back into the vent plug's main body through baffle to come back inside the cell. Hence, the leakage will not come out in a stipulated time duration as long as possible.
Washer: Washers used in this is an acid resistant, oxidation resistant and heat resistant due to EPDM rubber usage and there is no color change /no shape change /leachable extract after testing. In Figure. 1, the main usage of rubber washer is to tighten the vent plug with cover properly and prevents spillage from the vent plug through the added thread designs. EPDM rubber helps for lasting long time in the acidic environment due to its lower acid loss property.
Baffle: Baffle is designed with locking to avoid the unnecessary spillage of an electrolyte. And inside the baffle there is a path from where the gases moves upwardly and struck on PP disc & baffle wall itself which then condenses and get back into the cell in the liquid form. This is the main reason for lower water loss. No need for the regular top-up of water in the battery. In case our battery is tilt at 90-degree Angle, this long baffle will limit the access for flow of electrolyte on the vent wall by the locking as shown in Figure. 1 (part 5). This baffle also works as a closed chamber.
Vacant Space: As shown in Figure. 1 (part 7 & 9), the vacant space was given at the two places along side the circumferential space of the main body. They play a very important and critical role in the vent plug. Along with the hydrogen gases, steam presence will also be there. When the temperature gets reduced, steam gets condensed in the vacant space provided. After condensation, they get back into the cell to join the electrolyte.
Results of the newly designed vent plugs shows that the leakage time gets extended was to 8 hours from the time of tilting on the angle of 90° and accordingly the present vent plugs are reliable and suitable for the stationary applications. Also, in over-charging condition, it will prevent the leakage.
It is mandatory to check the leakage from the vents plugs after 24 hours. Because vent plugs will have the possibility of getting blocked and results in

battery bulging. Bursting is also possible in case of the higher internal pressure and the external spark may occur due to the gas accumulation inside the cell.
This special Vent Plug resists the electrolyte spillage when battery also put to 45° to 90° angle . When keep this battery to 45° to 90° angle for 60 minutes, it was observed that there is no leakage of electrolyte from the Vent Plugs of all vent hole of cells.
In order to perform the test of spillage, the inventors have carried out the following test.

Test a) Charging Test
Acceptance Criteria
There should not be any leakage of electrolyte from vent plugs.
Observations:
Tilted the battery at 90°-angle from vertical position up to 60 minutes.
After conducting this test, we have found no leakage at the surface of battery in given time.
Test b) Battery Tilt Test
Take The Fully Charged Battery
Fully Tighten the sample vent plug as provided
Tilt the Sample battery under test in the 90° direction for Least 1 hour duration
Acceptance Criteria
There should not be any leakage of minutes electrolyte from vent plugs up to 60
As it is apparent to those skilled in the art, various alterations and modifications can be made to this invention in retrospect thereof.

We Claim:

1. A vent plug comprises of
a main body, a baffle, a washer, and a disc wherein the washer is provided below the top of the main body and a vacant space is provided along side the circumferential boundary of the main body from the baffle.
2. A vent plug as claimed in claim 1, wherein the disc is porous having the porosity around 35 to 43%.
3. A vent plug as claimed in claim 1, wherein a gap is provided between the external surface of the main body of the vent plug and the baffle along side the circumferential wall of the main body.
4. A vent plug as claimed in claim 1 wherein the disc is placed within the main body within one minute time duration with press fit tool to fix it with the main body during shrinkage.
5. A vent plug as claimed in claim 1, wherein the process of manufacturing the vent plug includes placing the disc within the main body within one minute time duration with press fit tool to fix it with the main body during shrinkage.
6. A vent plug as claimed in claim 1 wherein the vent plug reduces the electrolyte leakage or drain back of the electrolyte.
7. A vent plug as claimed in claim 1 which has a gas hole to let the gas pass through it during the motion or tilting.
8. A vent plug as claimed in claim 1, wherein the vent plug withhold the leakage of electrolyte in a battery when tilted at 45 degree to 90 degree.