FIELD OF THE INVENTION
The present invention relates to the field of batteries and in particular, the present invention relates to a self-locking bottom bar for a tubular plate battery.
BACKGROUND OF THE INVENTION
Storage of electrical energy is an important aspect in almost all facets of the contemporary technological world. Electrical energy can be stored in storage devices such as batteries, wherein the electrical energy can be utilized wherever required.
A typical battery comprises a container, wherein at least one positive electrode, at least one negative electrode, one or more separation membranes and electrolyte are housed.
Typically, the positive electrode comprises a plurality of tube or tubular like portions. The tubes are made of non-woven material and are configured to retain active material. The active material may be a material such as lead oxide. Further, a spine is received in each of the tubes, the spines being made of lead. The spines extend along the length of the tubes. A first end of each of the spines is coupled to a common conducting bar, the common conducting bar being disposed over an operative top end of the tubes.
At the operative bottom end of the tubes, a plug or stopper is provided, wherein the plug or stopper is employed to cover or seal the operative

bottom end of the tubes. This helps in preventing egress of the active material contained within the tubes. The plug or stopper can be disposed on a bar, referred to as bottom bar, which aids in fitting of the plugs easily in to the operative bottom ends of the tubes.
Further, the conventionally known plugs or stoppers are provided with a depression or a hollow dip extending from an operative top surface of the plug or stopper. A second end of the each of the spines is received in the depression or the hollow dip.
One drawback of the conventionally known bottom bars with the plugs or stoppers, the provision of the depression or the hollow dip requires that the length of the spines has to be increased so that the second end of the spines is received in the depressions. However, this necessarily increases the amount of spine material and hence the cost.
Another drawback of the conventionally known bottom bars with the plugs or stoppers is that during the operation, the temperature of the battery increases owing to the reactions with the battery, which in turn results in increase in the length of the spines due to expansion. This may result in stress generation in the spines. Due to the expansion in spine length, there is a possibility that the bottom bar may be displaced away from the tube ends slightly. This in turn may lead to egress of the active material.
Further, in order to prevent egress of the active material from the tubes, it is necessary that the tubes are sealed over the stoppers or plugs by

techniques such as heat sealing or the like. This requires additional step of sealing the tubes with the stoppers or plugs. Also, special tool and skill is required for the sealing. This is not desired.
There is, therefore, felt a need to provide a self-locking bottom bar for a tubular plate battery that overcomes one or more drawbacks discussed herein above associated with the conventionally known bottom bars.
OBJECTS OF THE INVENTION
Some of the objects of the presently disclosed invention, of which at the minimum one object is fulfilled by at least one embodiment disclosed herein, are as follows:
It is an object of the present invention to solve at least one problem of the prior art or to provide a useful substitute;
An object of the present invention is to provide a bottom bar for a tubular plate battery;
Another object of the present invention is to provide a bottom bar for a tubular plate battery, wherein the bottom bar is self-locking;
Still another object of the present invention is to provide a bottom bar for a tubular plate battery, which simple in make; and
Yet another object of the present invention is to provide a bottom bar for a tubular plate battery, which reduces the requirement of active material.

Other objects and benefits of the present invention will be more apparent from the following description, which is not intended to bind the scope of the present invention.
SUMMARY OF THE INVENTION
The present invention relates to a self-locking bottom bar for a tubular plate battery. The self-locking bottom bar of the present invention overcomes one or more drawbacks associated with the conventionally known bottom bars.
In accordance with an aspect of the present invention, the self-locking bottom bar comprises a body having a first end, a second end, an operative top surface, and an operative bottom surface, a plurality of bases extending from the operative top surface of the body, each of the plurality of bases having an operative top surface, and a plurality of projections extending from the operative top surface of the plurality of bases, at least one collar depending from a free end of each of the plurality of projections.
Further, the plurality of projections along with the collars is configured to engage with the tubular plate or gauntlet of the battery to prevent removal of the tubular plate or gauntlet and to prevent egress of active material from the tubular plate or gauntlet.

In accordance with another aspect of the present invention, a battery is provided, wherein the battery comprises a container, a lid disposed over an operative open to end of the container, at least one positive electrode and at least one negative electrode, wherein the positive electrode comprises a gauntlet defining a plurality of tubes, the plurality of tubes having an operative top end and an operative bottom end, a spine received within each of the plurality of tubes, the spine extending along the length of the tubes, an active material disposed within the plurality of tubes surrounding the spine, a self-locking bottom bar received with the operative bottom ends of the tubes, the bottom bar comprising, a body having a first end, a second end, an operative top surface, and an operative bottom surface, a plurality of bases extending from the operative top surface of the body, each of the plurality of bases having an operative top surface and a plurality of projections extending from the operative top surface of the plurality of bases, at least one collar depending from a free end of each of the plurality of projections, wherein the plurality of projections along with the collars is configured to engage with operative bottom ends of tubes to prevent removal of the tubes therefrom; and/or to prevent egress of the active material from the tubes.
BRIEF DESCRIPTION OF THE ACCOMPANYING DRAWING
The embodiments herein will be better understood from the following detailed description with reference to the drawing, in which:

FIG. 1A illustrates a schematic line drawing of a bottom bar for a tubular plate battery in accordance with an embodiment of the present invention;
FIG 1B illustrates a front view of the bottom bar of FIG. 1 A;
FIG. 1C illustrates a schematic top view of the bottom bar of FIG. 1 A;
FIG. 1D illustrates a zoomed in front view of the bottom bar of FIG. 1 A;
FIG. 1E illustrates a schematic side view of the bottom bar of FIG. 1 A; and
FIG. 1F illustrates a zoomed in schematic top view of the bottom bar of FIG. 1A.
LIST OF NUMERALS

100 Bottom bar
102 - Body
104 First end
106 Second end
108 Operative top surface
110 Operative bottom surface
112 Plurality of bases
112a ■ Operative top surface (not matching with
description)
114 Plurality of projections
114a ■ Free end

116 - Collar
DETAILED DESCRIPTION OF THE PRESENT INVENTION
As described herein above in the background section, there are certain drawbacks associated with the conventionally known bottom bars with the plugs or stoppers, wherein the provision of the depression or the hollow dip requires that the length of the spines has to be increased so that the second end of the spines is received in the depressions. However, this necessarily increases the amount of spine material and hence the cost.
Further, during the operation, the temperature of the battery increases owing to the reactions with the battery, which results in increase in the length of the spines due to expansion. This may result in stress generation in the spines. Due to the expansion in spine length, there is a possibility that the bottom bar may be displaced away from the tube ends slightly. This in turn may lead to egress of the active material.
Further, an additional step of sealing the tubes with the stoppers or plugs is required, which also requires special tool and skill.
Accordingly, the present invention provides a bottom bar for a tubular battery which overcomes one or more drawbacks associated with the conventional bottom bars. More specifically, the present invention provides a self-locking bottom bar for a tubular plate battery.

The present invention is described herein with reference to the accompanying drawing, wherein FIG. 1A illustrates a schematic line drawing of a bottom bar for a tubular plate battery in accordance with an embodiment of the present invention; FIG 1B illustrates a front view of the bottom bar of FIG. 1A; FIG. 1C illustrates a schematic top view of the bottom bar of FIG. 1A; FIG. 1D illustrates a zoomed in front view of the bottom bar of FIG. 1A; FIG. 1E illustrates a schematic side view of the bottom bar of FIG. 1A; and FIG. 1F illustrates a zoomed in schematic top view of the bottom bar of FIG. 1 A.
In accordance with an aspect of the present invention, the self-locking bottom bar 100 for a tubular plate battery comprises a body 102 having a first end 104, a second end 106, an operative top surface 108, and an operative bottom surface 110. The body 102 can have any shape and can be in the form of a bar. The body 102 can have a groove inscribed along a longitudinal axis thereof. The groove helps in handling and/or installation of the bottom bar 100. In an embodiment, the body 102 can be substantially rectangular in shape. Any other shape is also well within the ambit of the present invention. Typically, the operative top surface 108 and the operative bottom surface 110 are substantially flat. The flat bottom surface 110 aids in easy and simple installation/placement of the bottom bar along with the gauntlet or the tubes on to the bottom of a battery container. Further, the flat top surface 108 aids in adding further features which are described herein below.

The substantially flat top surface 108 further includes a plurality of bases 112 which extend therefrom. In an embodiment, the plurality of bases 112 extends integrally from the operative top surface 108. In an embodiment, the plurality of bases 112 is substantially cylindrical in shape. The plurality of bases 112 has an operative top surface 112a.
In accordance with the present invention, a plurality of projections 114 extends from the operative top surface 112a of the plurality of bases 112. The plurality of projections 114 has a typical profile, wherein the plurality of projections 114 engages with the tubes (not shown in the figures) of the gauntlet or the tubular plate (also not shown in the figures), such that there is no need of any heat sealing. Once the projections 114 are received in the operative bottom ends of the tubes, the projections engage with the walls of the tubes. Further, the operative top surfaces 112a of the plurality of bases 112 are substantially flat such that the ends of the tubes are received thereon in tight fitting configuration so that leakage or egress of the active material from the tubes can be prevented.
In accordance with an embodiment, the projections 114 have at least one collar 116 depending from a free end thereof. The number of collars 116 can be in the range of 1 to 10. In a preferred embodiment, the number of collars 116 can be four. The number of collars 116 can vary. The collars 116 are the ones which engage with the walls of the tubes. The projections 114 along with the collars 116 engage with the tube to prevent

removal of the tubular plate or gauntlet and/or to prevent egress of active material from the tubular plate or gauntlet.
In an embodiment, the projections 114 have a cross-section, which is substantially trapezoidal in shape. The projections 114 can have any other shape and is not limited to trapezoidal shape.
In an embodiment, the body 102, the bases 112, the projections 114 and the collar 116 are integral. The bottom bar 100 can be molded employing polymers such as polypropylene, but is not limited to polymers.
In an embodiment, the bottom end of a spine is spaced apart from the free end 114a of the projections 114. The gap between the bottom end of the spine and the free end 114a of the projections 114 can be in the range of 0.5 mm to 3 mm. Typically, the gap can be 1 mm in length. The provision of the gap helps in preventing the stress generated in the spines on expansion due to heating.
In another aspect of the present invention, a battery is provided wherein the battery comprises a container, a lid disposed over an operative open to end of the container, at least one positive electrode and at least one negative electrode, wherein the positive electrode comprises, a gauntlet defining a plurality of tubes, the plurality of tubes having an operative top end and an operative bottom end, a spine received within each of the plurality of tubes, the spine extending along the length of the tubes, an active material disposed within the plurality of tubes surrounding the spine,

a self-locking bottom bar 100 is received within the operative bottom ends of the tubes, the bottom bar 100 comprising, a body 102 having a first end 104, a second end 106, an operative top surface 108, and an operative bottom surface 110, a plurality of bases 112 extends from the operative top surface 108 of the body 102, each of the plurality of bases 112 having an operative top surface 112a, and a plurality of projections 114 extends from the operative top surface 112a of the plurality of bases 112, at least one collar 116 depending from a free end 114a of each of the plurality of projections 114, wherein the plurality of projections 114 along with the collars 116 is configured to engage with operative bottom ends of tubes to prevent removal of the tubes therefrom; and/or to prevent egress of the active material from the tubes.
TECHNICAL ADVANCES OF THE PRESENTLY DISCLOSED INVENTION
The presently disclosed invention, as described herein above, provides several advances including, but that are not limited to, a bottom bar for a tubular plate battery, wherein the bottom bar:
- is self-locking;
- is simple in make;
- reduces the spine length, which has no role to play in the battery capacity or battery life optimize the spine lead which is not participating in battery capacity or life;
- improves area of contact of spine.

WE CLAIM:
1. A self-locking bottom bar for a tubular plate battery, said bottom bar
comprising:
- a body having a first end, a second end, an operative top surface, and an operative bottom surface;
- a plurality of bases extending from said operative top surface of said body, each of said plurality of bases having an operative top surface; and
- a plurality of projections extending from said operative top surface of said plurality of bases, at least one collar depending from a free end of each of said plurality of projections.
2. The bottom bar as claimed in claim 1, wherein said body is rectangular
in shape and is in the form of a bar.
3. The bottom bar as claimed in claim 1, wherein said plurality of bases is
cylindrical in shape.
4. The bottom bar as claimed in claim 1, wherein the number of said
collars is four.
5. The bottom bar as claimed in claim 1 is made of polypropylene.

6. The bottom bar as claimed in claim 1, wherein said projections having a
cross-section, which is substantially trapezoidal in shape.
7. The bottom bar as claimed in claim 1 having a height which is such that
a gap is defined between an operative bottom end of a spine and said free end of said projections of said bottom bar.
8. The bottom bar as claimed in claim 7, wherein said gap is having length
in the range of 0.5 mm to 3 mm.
9. The bottom bar as claimed in claim 1, wherein said plurality of
projections along with said collars is configured to engage with said tubular plate or gauntlet of said battery to prevent removal of said tubular plate or gauntlet and to prevent egress of active material from said tubular plate or gauntlet.
10. A battery comprising:
- a container;
- a lid disposed over an operative open to end of said container;
- at least one positive electrode and at least one negative electrode, wherein said positive electrode comprises:

o a gauntlet defining a plurality of tubes, said plurality of tubes having an operative top end and an operative bottom end;
o a spine received within each of said plurality of tubes, said spine extending along the length of said tubes;
o an active material disposed within said plurality of tubes surrounding said spine;
- a self-locking bottom bar received with said operative bottom ends of said tubes, said bottom bar comprising:
o a body having a first end, a second end, an operative top surface, and an operative bottom surface;
o a plurality of bases extending from said operative top surface of said body, each of said plurality of bases having an operative top surface; and
o a plurality of projections extending from said operative top surface of said plurality of bases, at least one collar depending from a free end of each of said plurality of projections, wherein said plurality of projections along with said collars is configured to engage with operative bottom ends of tubes

■ to prevent removal of said tubes therefrom; and/or
■ to prevent egress of said active material from said tubes.