FIELD OF INVENTION
This invention relates to an improved cap for lead acid battery to
improve battery performance. More particularly, the present
invention reduces the water consumption during battery charging
and discharging, acts as mist eliminator and controls the discharge
of gases from the battery during charging operation.
PRIOR ART
The most prominent rechargeable, storage battery for ignition and
emergency power uses is the lead-acid battery comprisirig of a
plurality of cells, each containing opposed vertical lead and lead
dioxide electrode plates immersed in aqueous sulfuric acid electrolyte.
The lead-acid battery must be vented since gases develop during
charge and discharge. The vent openings permit water to evaporate
from the electrolyte. In case too much water evaporates, the electrolyte
level recedes past the top of the electrode plates and the electrode
paste can dry, flake off or become irreversibly affected such as by
oxidation of the lead. If too much electrode material flakes off, it can
collect at the bottom and form a bridge short-circuiting cell. A shortcircuit
of only one cell is sufficient to render the lead -acid battery
useless.
Too much water is also undesirable since that can leak acid onto and
behind the battery casing and corrode the pan below the battery and
the fenderwall next to the battery. It also can cause corrosion of the
terminals and cables. Many batteries fail by corrosion and severing of
the terminals from the intemal connectors to the cell electrodes.
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Reference may be made to the following known arts:
US Patent no 5,284,720 relates to the explosion attenuating vent cap
for storage batteries. The present invention features an electrolyte
drain and baffle design adapted for maximizing return to the battery of
any liquid which may enter the vent from vibration, tilting,
overheating, overcharge and the like
Publication no CN201898155 relates to a battery cap for a lead acid
storage battery, which belongs to a part in the lead acid storage
battery. The present lead acid storage battery cap has an
unreasonable structure and a poor safety performance. The battery
cap of the lead acid storage battery comprises a battery cap main
body, wherein a safety valve and an explosion-proof air ftlter plate
mounting hole are arranged in the battery cap main body, and the
safety valve is arranged right below the explosion-proof air ftlter plate
mounting hole.
US Patent no 6,461,758 is directed to an improved vent cap system for
use in an electrochemical battery is provided which includ~s a· ring
flange for forming a ring seal between the vent cap assembly and the
fill tube. When the vent cap assembly is positioned in the battery
housing, the ring flange and the fill tube deform to create a seal
therebetween to provide a fluid tight seal.
US Patent no 6,143,438 discloses an improved vent cap system for
use in an electrochemical battery is provided which includes a ring
flange for forming a ring seal between the vent cap assembly and the
fill tube. When the vent cap assembly is positioned in the battery
housing, the ring flange and the fill tube deform to create a seal
therebetween t~ provide a fluid tight seal.
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US Patent no 5,132,175 relates to vent cap includes a hollow vent
cover which is inserted into a battery vent hole and a flange which
retains the vent cap from over insertion into the vent hole. An ..,
aperture near the top of the vent cap communicates with the hollow
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interior of the vent cover and forms an exhaust path for discharge of
gases from within the battery.
US Patent no 5,209,992 relates to water by-passing, submersible,
flame retardent vent plug adapted for use in storage batteries of the
type containing liquid electrolyte. The plug has inlet and outlet slots
and a hollow portion providing a gas communication path. A porous
flame arrester is positioned in the path. A circular raised seat is
positioned in the path between the flame arrester and the outlet slots
to allow water from the battery's exterior which enters the outlet slots,
to exit the vent plug without entering the battery.
US Patent no 4,098, 963 relates to a vented cap for a multiple cell
storage battery which comprises a base member having a plurality of
integrally molded vent plug portions adapted to fit into individual filler
wells of the battery and a cover member which snaps in place over the
base member to form a chamber for gas egressing from the battery.
US Patent no 4,562,127 relates to an indicator cap (22 or 80) formed
of a base connected to a transparent tube (46) forming a cylindrical
cavity (48) receiving a colored or opaque float (70). The position of the
float (70) within the tube (46) indicates the level of the electrolyte in
the cell (20) of the battery (10).
US Patent no 6294282 relates to a vent valve which is capable of
mechanical attachment to a lead acid battery through vent hole
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structure provided in the case cover. The vent valve is a molded hollow
tubular housing having a cup portion, the bottom of which rests atop
the battery case, and a neck portion extending through an opening
into the battery case.
US Publication no 20110111274 relates to a vent cap which includes
an internal vent well and an external mounting flange. The internal
vent well may be comprised of a hollow cylindrical tube sized to accept
a watering gun nozzle therein. The internal vent well may include a
variety of elements that limit an insertion depth of the watering gun
nozzle. In ohe embodiment, the internal vent well may comprise at
least a first ,section and a second section.
US Publication no 20060141342 relates to a vent cap for mounting in
a fill opening of an electrochemical battery. The cap includes a hollow
cap body with connected top and bottom walls and an inlet aperture
adjacent one end of the bottom wall. The body forms a material
holding chamber and has a vent hole spaced away from the inlet
aperture. A connector is provided on the bottom wall for attachably
mounting the cap body over a fill opening.
Publication no CN101540388 relates to a multifunctional liquid
injection cap of a lead acid storage battery for traction. The cap
comprises a shell (1), a liquid level control device and a cap cover,
wherein the top of the cap cover is provided with a liquid injection hole
(III), and the lateral surface of the cap cover is provided with an
exhaust hole (IV), a pane~ (12) and a floater viewing port translucent
cover (4).
0,
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US Publication no 2010323229 relates to the battery vent cap capable
of push-in installation and tum-out removal. The cap includes
bayonet tabs. The tabs in tum each include a ramp portion to
facilitate movement of the cap bayonet tabs past bayonet tabs in a
battery vent port as the vent cap is inserted into the port axially
without substantial rotation.
Publication no CN201153131 relates to the smooth anti-backfire lead
acid storage battery cover which belongs to the storage battery
technical field and is used for solving the problem that a storage
battery is easy explosive when suffering from open flame under the
charging condition
US Publication no US2001031390 relates to the battery cap for
engagement in a fill port of a cell of a deep cycle, lead-acid electrical
storage battery. The battery cap is formed of a hollow, tubular body
having an upper end with an expansive mouth opening, and a lower
end at which a transverse floor extends radially inwardly. The floor
includes a central, annular convex downwardly projecting portion that
defines a central fluid passage opening.
Reference may be made to a product entitled "Water miser battery
vent cap" by "Maverick Solar". The product is a Water Misers are
molded plastic "flip~top" vent caps designed to reduce and ease
maintenance on flooded Lead-Acid batteries. There is no need to
remove the caps when charging, filling or equalizing the batteries.
When charging, the plastic pellets capture up to 90% of the moisture
and acid droplets. This reduces acid fumes, corrosion, and keeping
the battery tops much cleaner and dryer. Excess water is dropped
back into the battery cell.
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None of the patent status above talks about a cap which can be used
for float sensing along with the mist elimination. Thus, there exists
the need of an improved cap which has float sensor along with the
mist elimination. Also as disclosed in the conventional method
wherein the mist eliminator is removed and vent plug is again put on, :twhich
increases the operational time
In order to overcome the above listed prior art, the present invention
provides an improve~ cap for lead acid battery with mist eliminator
and float sensor.
OBJECTS OF THE INVENTION
The primary object of the present invention is to provide an improved
cap for lead acid battery to improve battery performance by controlling
evaporation of water.
Another object of the present invention is to provide an improved cap
for lead acid battery to improve battery performance, which eliminates
the need of float sensor in the battery
Still another object of the present invention is to provide an improved
cap for lead acid battery to improve battery performance which is easy
to handle and cost effective
Yet another object is to provide an improved cap for lead acid battery
to improve battery performance which is multi functional thereby
eliminating use of three different caps at different stages of battery
manufacturing and usage.
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Another object it to increase productivity which leads to battery
manufacturing cycle time reduction, inventory reduction, BOM
reduction and reduced handling.
Still another object of the present invention is to provide an improved
cap for lead acid battery which significantly eliminates the need of
topping the water into the battery.
Yet another object of the present invention is to provide an improved
cap for lead acid battery which reduces the water consumption.
SUMMARY OF THE INVENTION
Accordingly the present invention provides an improved battery cap
for lead acid battery. The improved cap comprises mist eliminator and
float sensing unit which eliminates the need of the float sensor in the
battery.
The battery cap of the invention has the provision of a top collar on
the float which engages a stop to prevent the float from falling into the
cell and which can close the vent in its highest position.
The cap is a multi-purpose plastic moulded flip-top device which
functions as mist eliminator c1.1,m vent cap cum float sensor indicating
acid level to help top up the battery when required.
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The cap is provided with the battery in packed form and can be
reversed to become a float sensor thereby helping user know the acid
level in use and also to top the battery when required.
STATEMENT OF INVENTION
According to this invention, there is provided an improved cap for
lead acid battery to improve battery performance comprising of a
hollow body member and a float member slidingly mounted in the
body member, wherein said body member houses a mist eliminator
and said float member accommodates a float sensing unit.
BRIEF DESCRIPTION OF THE ACCOMPANYING DRAWINGS
Further objects and advantages of this invention will be more
apparent from the ensuing description when read in conjunction with
the accompanying drawings and wherein:
Fig. lA shows: front view of cap of the present invention.
Fig. lB shows: cap of the present invention in two parts.
DETAILED DESCRIPTION OF THE INVENTION WITH REFERENCE
TO THE ACCOMPANYING DRAWINGS:
The present invention discloses an improved cap for lead acid battery
to improve battery performance. Now, reference may be made to fig. 1,
wherein said cap comprising of a hollow body member having a
cylindrical cavity (3) and a cylindrical opaque or coloured float
member (4) slidingly mounted in the cavity, which moves up and down
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according to the electrolyte level. The upper part (3) houses a mist
eliminator (1) and the lower part (4) accommodates a float sensing
unit (2), which eliminates the requirement of float sensor in the
battery.
The upper portion 3 of the cap is transparent or opaque and the lower
section is provided with threads or a plug-like rim 5 for liquid-tight
receipt in the opening in the cell. A filter 6 is provided between the rim
5 and mist eliminator 1. A vent (V) can be provided on the side wall of
the cap in communication with the cell through the cavity. The
downward slope of the vent prevents ingress of water from hoses or
water cans since the vent opening is baffled by the lower face of the
opening. Further, there is provision of a top collar (F) on the float (2)
which engages a stop to prevent the float from falling into the cell and
which can close the vent in its highest position.
The cylindrical cavity (3) is detachable from float member (4) as shown
in fig. lB. Thus, the new improved cap is a multi-purpose plastic
moulded flip-top device (as shown in fig. lB) which functions as mist
eliminator 1 cum vent cap cum float sensor 2 indicating acid level to
help top up the battery when required. It facilitates manufacturing
and assembling of the battery after acid filling and leveling. The
present invention eliminates the need to put a normal/ conventional
vent plug followed by removal before charging and replacing it with a
mist eliminator cap. Instead a single multi-functional, cap of the
present invention can be put after acid filling and leveling and before
charging. Thereafter, the charging can continue. However, after
charging, there is no need to remove this cap, as done during the
conventional method wherein the mist eliminator is removed and vent
plug is again put, thereby
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reducing operational time. Also, said cap captures the moisture and
acid droplets & reduces acid fumes, corrosion, and keeps the battery
tops much cleaner and dryer. Excess water is dropped back into the
battery cell. Hence, there is no need to remove the caps when
charging, filling or equalizing the batteries.
The cap is provided with the battery as packed and can be reversed to
become a float sensor thereby helping user know the acid level in use
and helps to top the battery when required.
The cap is compatible with all existing batteries and can be provided ·
as an original equipment cap or can be substituted for the caps of
batteries in service. The present invention controls the evaporation of
the water, eliminates the need of topping the water onto the battery
and reduces the water consumption.
It is to be noted that the present invention is susceptible to
modifications; adaptations and changes by those skilled in the art.
Such variant embodiments employing the concepts ru:;td features of
this invention are intended to be within the scope of the present
invention, which is further set forth under the following claims:-

WE CLAIM; %
1. An improved cap for lead acid battery to improve battery
performance comprising of a hollow body member and a float
member slidingly mounted in the body member, wherein said
body member houses a mist eliminator and said float member
accommodates a float sensing unit.
2. An improved cap for lead acid battery to improve battery
performance as claimed in claim 1, wherein the hollow body
member having a cylindrical cavity and the float member is
opaque or coloured cylindrical/rectangular member, which *
moves u p and down according to the electrolyte level.
3. An improved cap for lead acid battery to improve battery
performance as claimed in claim 1 or 2, wherein the hollow body
member is transparent or opaque. *
4. An improved cap for lead acid battery to improve battery
performance as claimed in any of the preceding claims, wherein
the float member is provided with a plurality of threads or a
plug-like rim for liquid-tight receipt in the opening of the cell.
5. An improved cap for lead acid battery to improve battery
performance as claimed in any of the preceding claims, wherein
a filter is provided between the rim and mist eliminator.
6. An improved cap for lead acid battery to improve battery
performance as claimed in any of the preceding claims, wherein
a vent is provided on the side wall of the cap in communication
with the cell through the cavity such as herein described.
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7. An improved cap for lead acid battery to improve battery
performance as claimed in any of the preceding claims, wherein
a top collar is provided on the float which engages a stop to
prevent the float from falling into the cell and can close the vent
in its highest position.
8. An improved cap for lead acid battery to improve battery
performance as claimed in any of the preceding claims, wherein
the cylinder cavity is detachable from said float member.
9. An improved cap for lead acid battery to improve battery
performance as claimed in any of the preceding claims, which
functions as mist eliminator cum vent cap cum float sensor
indicating acid level to help top up the battery when required.
10. An improved cap for lead acid battery to improve battery
performance as claimed in any of the preceding claims, wherein
the cap captures the moisture and acid droplets 86 reduces acid
fumes, corrosion, and keeps the battery tops much cleaner and
dryer and eliminates need to remove the caps when charging,
filling or equalizing the batteries, in which the cap controls the
evaporation of the water, eliminates the need of topping the
water into the battery and reduces the water consumption.