INTEGRATED ENERGY STORAGE ENCLOSURE FOR BATTERY BANKS
FIELD OF THE INVENTION
The present invention relates in general to climate-controlled enclosures for electrical devices and in particular to an integrated energy Storage enclosure for the storage of battery banks. It discloses a battery bank storage enclosure for maintaining the temperature within the battery enclosure, an automated refilling system for adding water to the flooded lead acid (FLA) batteries and a load controller that controls the output voltage of the batteries connected to the electrical loads.
BACKGROUND AND PRIOR ART
At remote areas, reliable source of power is required. As electric power outages are undesirable, to ensure continuous power supply backup power supplies like lead acid batteries are used at telecom sites. These batteries at the base stations are housed in an enclosure. Batteries store electrical energy using chemical reaction and can be hazardous if they are improperly handled or contained. A battery is an electrical device consisting of two or more electrochemical cells that converts stored chemical energy into electrical energy. Rechargeable batteries can be charged, discharged into the loads and recharged again many times from any energy source, as compared to non rechargeable batteries. Lead Acid Batteries are commonly used as rechargeable batteries which provide higher energy densities. In a photovoltaic system, lead acid batteries designed using deep cycle cells are provided where the batteries are regularly discharged and less subjected to degradation due to cycling. Flooded Lead Acid (FLA) Batteries using deep cycle cells consists of flat lead plates in a pool of electrolyte.
A battery cell consists of a positive lead plate covered with a paste of lead dioxide and a negative plate made of sponge lead and an insulating material called separator in between them. A battery contains two or more electrochemical cells that are completely immersed into an electrolyte which is a combination of sulphuric acid and distilled water. When fully charged batteries are connected to the loads, the chemical reaction between the electrodes and electrolyte happens and both the plates begin to coat with a substance called lead sulphate (sulphating). While the discharge continues, the plates get more coated resulting a sharp decrease in the battery voltage. When the plates get almost coated, the discharge discontinues and the battery voltage will be low. Therefore the batteries need to be

recharged to break the sulphating. The battery voltage is gradually increased by constant recharging from an energy source. While recharging the batteries, gassing occurs and as a result water in the electrolyte gets vaporised and the acid gets accumulated at the bottom of the battery. This condition is known as Battery Stratification. Equalization is the only solution for reducing battery stratification and for the equalization process water need to be added in the batteries. The electrolyte level in the batteries should be just below the bottom of the vent well and above the flat lead plates.
In the prior art, battery enclosures are made of different materials. Plastic battery enclosures are very common, cheap, light and corrosion resistant. But they deteriorate in sunlight and ultimately break down, and are not very strong. Wood is a good choice because it is non-conductive and prevents an electrical short circuit between an exposed battery terminal or cable and the enclosure. One shortcoming of using wood is that, over time, leaked or spilled battery electrolyte undermines its structural integrity. Plywood, which is relatively light andstrong, is another material used to make a battery enclosure, but the disadvantage is that it might rot if not protected continuously. Usage of concrete for making enclosures is also known, as it results in structures which are very strong, and can be built underground in order to maintain steady temperatures. The major disadvantage associated with these structures is that these structures are heavy and difficult to construct in remote installation sites.
Hydrogen venting is another prime issue concerned with battery enclosure. The main objectives of a ventilation system are management of environmental air temperature, humidity and air quality. The risk involved in a lead acid battery is explosion when charging exceeds and they begin to produce hydrogen and oxygen. As hydrogen disperses-rapidly, it has to be removed to prevent accumulation. Because hydrogen is "lighter than air and will tend to concentrate at ceiling level", the National Electrical Code (NEC) suggests that "some form of ventilation should be provided at the upper portion of the structure. Most of the battery enclosures are provided with a vent at the top, so that the hydrogen inside the enclosure can be drained.
Chemical reactions internal to the battery are driven by voltage and temperature. Higher the battery temperature, the faster will be the chemical reactions. While higher temperatures can provide improved discharge performance the increased rate of chemical reactions will result in a corresponding loss of battery life. Also operating batteries at higher

temperatures can result in the shedding of active materials from the battery plates. The resulting sediment build up at the bottom of the case can lead to electrical short circuits. Battery capacity is temporarily diminished at low ambient temperatures, and deeply discharged batteries housed in unconditioned enclosures in cold climates are vulnerable to freezing, which can result in cracked cases, spilled electrolyte and destroyed batteries. The existing' battery enclosures employ active cooling methods in order to reduce the temperature inside the enclosure, The active cooling methods are those which use powered devices such as fans or pumps for heat transfer. In some cases, passive cooling methods are used in tandem with active cooling to function more effectively.
The water filling is achieved while the batteries are in charging mode or fully charged mode. The watering must be done periodically according to the discharge cycle and the battery bank requires a regular continual verification on specified parameters for the smooth functioning and high life span. The battery parameters will be the battery voltage, battery current, state of charge (SOC), specific gravity of each battery cell, battery temperature, emitted hydrogen level, battery electrolyte level and so on. So a person is required in sites where battery is installed and checking the parameters after each discharge. A programmed controller circuit is connected to the batteries for transmitting the signal to the users for monitoring battery bank and a water tank will be associated with a controller circuit for the smooth functioning of watering in batteries. The water tank will be filled manually depending on the battery operations. The energy supply to the electrical loads may be in an uncontrolled manner, so the loads get damaged due to over voltage or under voltage. This situation can be controlled using a Load Controller with the battery bank that controls the output voltage batteries connected to the loads.
Thus, there is a great need for an enclosure for storage batteries which is easy to construct at site, is cost-effective and does not use electricity.
The Integrated Energy Storage Enclosure for the storage of battery banks according to the present invention, which employs passive cooling and passive hydrogen venting, overcomes the disadvantages of the prior art described above.
OBJECTS OF THE INVENTION
The main object of the present invention is to provide an Integrated Energy Storage Enclosure (IESE), which is an enclosure for accumulating batteries in a single entity, to store maximum power from the source of energy and distribute power to the equipments connected.

Another qbject of the present invention is to provide thermal management to control the temperature within the enclosure.
Another objective of the present invention is to provide a chimney ventilation system for drainage of the emission of hydrogen gas evolved inside the enclosure.
Another object of the present invention is to provide a microcontroller that is programmed to provide instructions to the equipments, receive signals from the batteries and sensors for the proper watering of batteries and transmitting information to distinct locations.
Another object of the present invention is to provide a GPRS modem for transmitting battery data to particularlocations for continuous monitoring of the battery bank.
Another object of the present invention is to provide a Cloud Server along with the Cloud Database for receiving the data from the modem and transmitting the data to the respective locations.
Another object of the present invention is to provide an Application Interface for the access of battery data at any distinct location.
Another object of the present invention is to provide a Distilled Water Reservoir that may be kept inside or outside the enclosure in association with the battery bank for the water refilling of FLA batteries.
Another object of the present invention is to provide solenoid valves for controlling the flow of water in batteries.
Another objective of the present invention is to provide a water fed pump for pumping out the excess of water in the tubes.
Another objective of the present invention is to provide a valve assembly using the floating valves providing the water flow in batteries.
Another object of the present invention is to provide sensors for detecting the current condition of batteries and transmitting signal to the microcontroller.
Another object of the present invention is to provide DC Load Controller for controlling the flow of input voltage to the electrical loads.

How the foregoing objects are achieved will be clear from the following description. In this context it is clarified that the description provided is non-limiting and is only by way of explanation.
SUMMARY OF THE INVENTION
An Integrated Energy Storage Enclosure (IESE) for battery banks compromises of a battery bank, a plurality of thermally insulated walls, a slanting corrugated roof adapted to drain rainwater, a hydrogen vent anda plurality of air holes. A distilled water tank, solenoid valves, a water feed pump, a valve assembly with floating valves, a controller circuit unit containing a programmed microcontroller with, sensors, a load controller and a GPRS modem are also provided. The thermally insulated walls are provided with sandwich panels,
The sandwich panels consist of an inner insulation core between two thin layers, the inner insulation core being made up of polyurethane foam (PUF).
The hydrogen vent is covered by vent cover and is provided at the top of the enclosure for proper venting of hydrogen.
A plurality of air holes is provided at the bottom to facilitate drawing in cooler air from outside into the enclosure when hydrogen rises inside the enclosure.
Thevalve assembly with floating valves is placed in the respective positions of the vents of the batteries. The start and end points of the valve assembly are connected to a distilled water tank that may be kept inside or outside the enclosure and a level light sensor is fitted to battery to recognise the electrolyte level.
A top metal cover covers the slanting roof structure which is fitted with the hydrogen vent. The PUF panels are also covered by said structure.
The microcontroller is adapted both for transmitting the battery data to distinct locations and operating the water flow in the batteries.

BRIEF DESCRIPTION OF THE ACCOMPANYING DRAWINGS
The nature and scope of the present invention will be better understood from the accompanying drawings, which are by way of illustratPon of a preferred embodiment and not by way of any sort of limitation. In the accompanying drawings:-
Figure 1 is a schematic diagram illustrating the operation of the present invention.
Figure 2 is a sectional isometric side view of thelntegrated Energy Storage Enclosure (IESE) according to the present invention.
Figure 3 is a sectional top view of the enclosure (IESE).
Figure 4 is a sectional side view of the enclosure according to the present invention showing internal arrangement of the batteries within the enclosure.
Figure 5 is a flowchart illustrating the flow of programmed instructions in the microcontroller provided.
DETAILED DESCRIPTION OF THE INVENTION
Having described the main features of the invention above, a more detailed and non-limiting description of a preferred embodiment will be given in the following paragraphs with reference to the accompanying drawings.
In all the figures, like reference numerals represent like features. Further, the shape, size and nurnber of the devices shown are by way of example only and it is within the scope of the present invention to change their shape, size and number without departing from the basic principle of the invention.
Further,, when in the following it is referred to "top", "bottom", "upward", "downward", "above" or "below", "right hand side", "left hand side" and similar terms, this is strictly referring to an orientation with reference to the apparatus, where the base of.the apparatus is horizontal and is at the bottom portion of the figures. The number of components shown

is exemplary and not restrictive and it is within the scope of the invention to vary the shape and size of the apparatus as well as the number of its components, without departing from the principle of the present invention.
All through the specification including the claims, the technical terms and abbreviations are to be interpreted in the broadest sense of the respective terms, and include all similar items in the field known by other terms, as may be clear8to persons skilled in art. Restriction or limitation if any referred to in the specification, is solely by way of example and understanding the present invention.
The Integrated Energy Storage Enclosure for battery banks IESE (A) compromises of a battery bank (1) provided with thermally insulated walls(2) which are provided with sandwich panels (3), a slanting corrugated roof (4) to drain rainwater and a provision for hydrogen venting (5), a plurality of air holes (28), a distilled water tank (6), solenoid valves (7), water feed pump (8), a valve assembly (9)with floating valves (29), a controller circuit unit (33) containing a programmed microcontroller (10)with sensors (11), load controller (12)and GPRS modem (13).Cloud server (14) with cloud database (15) and multiple user interfaces (16) are peripheral to the IESE (A).
As shown in figure 1 of the drawings, the power from the PV panels (17) flows to the MPPT charge controllers (18) which regulate DC current and voltage to the loads (19) connected through the load controller (12). The programmable logic controller (20) communicates with all the.devices for the selection of electricity grid (21) and AC diesel generator (22) which is converted to DC from AC using the rectifiers (23) through common AC bus in the absence of solar energy. The output from the programmable logic controller (20) controls the flow of current and voltage to the loads (19) connected in addition to charging and discharging of the batteries (1) which are used as a backup in the sites. The battery readings of the specified parameters are fed to the programmed microcontroller (20) which transmits the .data to the cloud server (14). The cloud server (14) stores the data in the cloud database (15) and fetches to the multiple user interfaces (16) for accessing the battery data.
As shown in figure 2 along with figure 3, the walls (2) of IESE (A) are made of thermally conductive material, preferably aluminium. Sandwich panels (3) are used for making the walls (2). These are cost efficient elements that consist of an inner insulation core (24) between two thin layers (25). The inner insulation core (24s) is made up of polyurethane foam (PUF). The material has a low thermal conductivity, is not easily ignitable and has

negligible, water permeability. The slanting corrugated metal roof (4) is placed on top of the top metal frame (26). A hydrogen vent (5) provided at the top for proper venting of hydrogen is covered by means of a vent cover (27) to prevent the entry of water inside the enclosure (A). For proper hydrogen venting, a plurality of air holes (28) is provided at the bottom, so that after charging when hydrogen rises in the enclosure (A), it moves towards the vent (5) and cooler air from outside is drawn into the enclosure through the air holes (28) as a result of pressure difference.
As shown in figure3, the valve assembly (9) with floating valves (29) is placed in the respective positions of the vents of the batteries (1). The start and end points of the valve assembly (9) are connected to the distilled water tank (6) that may be placed inside or outside the enclosure and a level light sensor (30) is fitted to battery (1) to recognise the electrolyte level. At the start and end points of the valve assembly (9), solenoid valves (7) are connected for the start and stop of water to the valve assembly. The solenoid valve (7) at the starting point is connected to water flow sensor (31) and water feed pump (8) before reaching the floating valves (29). A shunt resistor (32) is connected to a battery (1) for measuring the strength of current in the batteries and passes on the signal to a programmed microcontroller (10). A controller circuit unit (33) is fitted to the IESE (A) and this unit (33) contains a programmed microcontroller (10), GPRS modem (13), load controller (12) and shunt resistor (32).
As shown in figure 4, the IESE (A) can be assembled at the remote telecom tower site; it consists of-a bottom frame (34), a top frame (26), a plywood base (35), side PDF panels (3), top metal cover (36), top corrugated sheet (4) and a vent cover (27). The batteries (1) are made to rest on the plywood base (35). The top (26) and the bottom (36) frames are fixed by means of corner flushing angles (37). The sandwich PUF panels (3) are of two types: two for the longer sides and two for the shorter sides. The outer flushing angles (37) are used at the corners, which rivet on to the side PUF panels (3). The top metal cover (36) covers the slanting roof structure (4).The PUF panels (3) are covered by the structure (4), which is'fitted with a hydrogen vent (5).
As shown in figure5, the microcontroller (10) is programmed both for transmitting the battery data to distinct locations and operating the water flow in the batteries (1). For operating the water flow in the batteries (1) two criteria are programmed in the microcontroller (10). The first condition is checkingthe electrolyte level in the batteries (1) which can be monitored using a level light sensor (30) that isHmmersed in the battery (1). When the level of electrolyte is low, a signal is triggered and transmitted to the

microcontroller (10), for making a confirmation whether the battery bank (1) is being fully charged. Charging is the second condition and this can be measured using the shunt resistor (32) which is connected in series with the batteries (1). When the shunt resistor (32) detects a positive value, the batteries (1) are in charging mode and if the shunt resistor (32) detects a negative value, the batteries are in discharging mode. When the conditions are satisfied, the microcontroller (10) transmits signals to the first solenoid valve
(38) to be opened, the water feed pump (8) to be operated and the second solenoid valve
(39) to be closed. The water starts to flow into the batteries (1) from the distilled water tank (6). When the battery (1) gets water filled, the tube (9) seems to be water logged and the water flow sensor (31) triggers a signal to the microcontroller (10). The microcontroller then transmits signals to the first solenoid valve (38) to be closed, the water fed pump (8) to be opened for two minutes for pumping out the water in tube (9) and the second solenoid valve (39) to be opened for the water to flow back to the water tank (6).
The present invention has been described with reference to some drawings and a preferred embodiment purely for the sake of understanding and not by way of any limitation and the present invention includes all legitimate developments within the scope of what has been described herein before and claimed in the appended claims.

I claim:
l.An Integrated Energy Storage Enclosure (IESE) for battery banks (A) comprising of a battery bank (l),a plurality of thermally insulated walls (2) enclosing the battery bank, a slanting corrugated roof (4) having a hydrogen vent (5) covered by vent cover (27) at the top adapted to drain rainwater, a plurality of air holes (28) provided at the bottom, a distilled water tank (6) placed inside or outside of the*enclosure, solenoid valves (7) located close to the enclosure, a water feed pump (8) and a valve assembly (9) with floating valves (29)placed in the respective positions of the vents of the batteries (1), a controller circuit unit (33) containing a programmed microcontroller (10), a load controller (12) and a GPRS modem (13) mounted on one face of the enclosure and sensors (11) located outside the enclosure, said thermally insulated walls (2) being provided with sandwich panels (3).
2.The enclosure (A) as claimed in claim 1, wherein said sandwich panels (3) consist of an inner insulation core (24) between two thin layers (25), the inner insulation core (24) being made up of polyurethane foam (PUF).
3.The enclosure (A) as claimed in claim 1, wherein said hydrogen vent (5) is covered by vent cover (27) and is provided at the top of the enclosure for. proper venting of hydrogen.
4.The enclosure (A) as claimed in claim 1, wherein said plurality of air holes (28) is provided to facilitate drawing in cooler air from outside into the enclosure when hydrogen rises inside said enclosure (A).
5.The enclosure (A) as claimed in claim 1, wherein the start and end points of said valve assembly (9) are connected to said distilled water tank (6) and a level light sensor (30) is fitted to battery (1) to recognise the electrolyte level.
6.The enclosure (A) as claimed in claim 1, wherein a top metal cover (36) covers said slanting roof structure (4) fitted with said hydrogen vent (5), said PUF panels (3) being covered by said structure (4).
7.The enclosure (A) as claimed in claim 1, wherein said microcontroller (10) is adapted both for transmitting the battery data to distinct locations and operating the water flow in the batteries (1).