Plant and method of curing electrodes for lead-acid accumulators

Abstract

A curing plant and method of curing electrodes for lead-acid accumulators (100) are described, comprising a curing chamber (3); at least one air treatment unit (2), at least one delivery assembly (4) and at least one suction assembly (5); - said delivery assembly (4) comprising an inner-distribution unit of air fluidically connected to said suction assembly (5) so as to form a circuit for air, characterized in that said inner-distribution unit comprises at least one distribution channel (7) arranged inside the curing chamber in the upper portion thereof and configured for feeding air into the upper portion of the curing chamber (3) and sending at least one portion of the air flow fed into the lower portion of the curing chamber (3); - said suction assembly (5) comprising an opening for suctioning air, arranged in the upper portion of said curing chamber (3); - said distribution channel (7) comprising a first converging section and a second straight section (7b) arranged consecutively to the first converging section (7a), said first section (7a) being configured for receiving the air entering the curing chamber (3); said second straight section being open at the bottom for feeding the air coming from the first section (7a) into the curing chamber (3) by directing it downwards; - said opening for suctioning air being away, in direction of the transverse axis, from said distribution channel (7) so that the flow of air entering from said distribution channel (7) crosses said curing chamber (3) in transverse direction and comes out through said suction assembly (5) once fed into the upper portion of the curing chamber (3) and sent towards the lower portion of the curing chamber (3).

Description

[0001] “Plant and method of curing electrodes for lead-acid accumulators”

[0002] Field of the Invention

[0003] The present invention generally concerns the technical field of processes of manufacturing electric accumulators. Specifically, the present invention concerns a plant and a method of curing electrodes for lead-acid accumulators.

[0004] Known art

[0005] Lead or lead-acid electric accumulators are the most widely used rechargeable electric accumulators in the world. They consist of positive and negative plates immersed in a solution of sulfuric acid (electrolyte). The positive plates are made of lead dioxide, whereas the negative plates are made of spongy pure lead.

[0006] To produce energy, a chemical reaction takes place inside the accumulator during the discharge stage, in which the electrolyte combines with the active material of the positive and negative plates, transforming it into lead sulfate. This resulting chemical compound is the lead salt of sulfuric acid and is in the form of white crystals or white powder, which is very poorly soluble in water: it is deposited on the plates during the discharge stage. When the entire electrolyte has chemically reacted with the plates, there is no more possibility of chemical reaction and the accumulator is discharged and must be recharged with energy. During the charging stage, the electric power supplied returns the active material of the positive and negative plates to its original condition. Specifically, lead sulfate is transformed back into metal lead and sulfuric acid in the negative plates and into lead dioxide and sulfuric acid in the positive plates.

[0007] Lines for the industrial production of lead or lead-acid electric accumulators are equipped with a plurality of equipment, which generally involve initially making a grid consisting of lead filaments. Typically, grids are made from a continuous lead alloy strip. The grids are then coated with a lead oxide paste by using a special coating machine. In the case of a continuous strip, the latter is covered on both sides with a layer of paper and then cut into pieces to form individual plates. Next, the individual coated plates are subjected to a kiln-drying process and then collected and stacked in bundles. The plate bundles are then stacked on pallets for the curing process, which takes place in special curing chambers, during which an exothermic reaction takes place to reduce the free lead in the active material and achieve proper crystallization and porosity, which have a direct influence on the performance of the accumulator.

[0008] Typically, inside the curing chambers, the curing process is divided into two: the wet phase during which the exothermic reaction of oxidation of the free metal lead in the mixture of the active plate material takes place, which needs temperatures between 35°C and 70°C with relative humidity from 75 to 99%, and a drying phase with temperature from 50°C to 90°C and relative humidity from 40% to 3%. The phases can last from 6 to 36 hours for the wet phase and from 2 to 48 hours for the drying phase, depending on the type of plates and oxide used in the mixture. Pallets with plates are placed inside the curing chamber, coming from the production line typically with operator-guided forklifts or by shuttles on rails and can be placed directly on the floor inside the chamber or on roller or chain conveyor systems for handling. The chambers can also be arranged in line to create a semi-continuous system in which one section is reserved for the wet phase and one section for the drying phase.

[0009] The Applicant noted that known curing chambers are characterized by a structure consisting of insulated vertical walls and roof panel, with ventilation units placed at the top and an access door placed at the front. Ventilation within the chamber may take place through perforated walls that extend the full height of the curing chamber with an air delivery side and an air suction side: in known curing chambers, perforated walls may have openings of various shapes and sizes and may be adjustable or may not have these perforated walls at all. The ventilation unit normally comprises, in the known chambers, an air heating unit by means of a direct or indirect natural gas burner, or finned electric resistances, one or more fans for circulating forced air, a fan for exhausting humid air in the curing and drying stages, a set of nozzles to humidify the air inside the chamber by injecting water with air or pressurized water or steam, a process control system with temperature and humidity probe to maintain the values required in the process controlled by PLC or microprocessor system. The Applicant noted that a limitation of known curing chambers currently used in the production process is due to the lack of control of air circulation in a precise and homogeneous manner on all pallets and, consequently, on all plates.

[0010] According to the Applicant this is, primarily, due to the design limitation of the known chambers with walls for the distribution of air within them, which consist of surfaces with pre-set openings that cannot be changed during the process and that are not designed for each individual type of pallet used in the production of lead-acid battery electrodes. The circulation of forced air that escapes from the perforated walls is sometimes not directed to the plates but passes between the gaps between the pallets or is directed to the structures of the pallets themselves, thus creating areas with less airflow within the chamber and thus less control over process parameters. Disadvantageously, the use of perforated walls increases the electric consumption of fans for forced air circulation because the pressure drop on the delivery and suction side increases exponentially in order to maintain air flow rates for process control. This directly affects the final quality of the plates with incomplete oxidation, uneven crystallization within the same chamber and different process temperatures affecting the final quality of the lead energy storage.

[0011] Also according to the Applicant, the use of perforated pre-set walls generates more condensation of humidity injected through nozzles with water or steam, because they have a lower temperature than the dew point and the delivery air speed results in condensation of airborne water droplets. Thus, object of the present invention is to solve or minimize the problems set forth above with reference to curing chambers for plates for lead or lead-acid electric accumulators of known types, by providing a drying plant and a curing method for electric accumulator plates, such that the plates can be cured in a more energy-efficient and process-controlled manner.

[0012] A further object of the present invention is to optimize the curing process of the plates that constitute the electrodes.

[0013] Another object is to have a more homogeneous active paste.

[0014] Another object is to save energy.

[0015] An additional object is to have a simpler process that can be implemented with a less expensive set of machinery.

[0016] Object of the invention is also to protect electrodes that exhibit the characteristic of performing better than those currently made, and to protect in particular electrodes made by the process it is intended to protect and the battery made with those electrodes.

[0017] Summary of the invention

[0018] Therefore the present invention, in its first aspect, concerns a curing plant of electrodes for lead-acid accumulators, which comprises a curing chamber, at least one air treatment unit, at least one delivery assembly, and at least one suction assembly;

[0019] - said delivery assembly comprising an inner-distribution unit of air fluidically connected to said suction assembly so as to form a circuit for air, characterized in that said inner-distribution unit comprises at least one distribution channel arranged inside the curing chamber in the upper portion thereof and configured for feeding air into the upper portion of the curing chamber and sending at least one portion of the air flow fed into the lower portion of the curing chamber;

[0020] - said suction assembly comprising an opening for suctioning air, arranged in the upper portion of said curing chamber;

[0021] - said distribution channel comprising a first converging section and a second straight section arranged consecutively to the first converging section, said first converging section being configured for receiving the air entering the curing chamber; said second straight section being open at the bottom for feeding the air coming from the first section into the curing chamber by directing it downwards;

[0022] - said opening for suctioning air being away, in direction of the transverse axis, from said distribution channel so that the flow of air entering from said distribution channel crosses said curing chamber (3) in transverse direction and comes out through said suction assembly, once fed into the upper portion of the curing chamber and sent towards the lower portion of the curing chamber.

[0023] By “upper portion” of the curing chamber is meant a portion that is placed more than 60% of the height above the floor of the curing chamber.

[0024] "Downward" or "to be bottom" is meant a generally vertical direction directed toward the floor or ground of the curing chamber.

[0025] In the aforesaid aspect, the present invention can have at least one of the preferred characteristics described hereunder.

[0026] Preferably, the curing chamber comprises at least one first deflector fin movable inside the curing chamber arranged below the distribution channel and configured for varying its inclination in order to help direct the flow of air to the upper or lower portion of the curing chamber.

[0027] Advantageously, the curing chamber comprises at least a second movable deflector fin arranged below the suction opening.

[0028] Preferably, the humidity-generating unit comprises a plurality of nozzles to spray pressurized water and feed it into the delivery assembly upstream of the distribution channel.

[0029] Conveniently, the humidity-generating unit comprises a high-pressure pump configured for pressurizing water to be sprayed and mixing it with ozone, and an ozone generator.

[0030] Preferably, the air treatment unit comprises at least one dehumidification system for dehumidifying the air fed into the curing chamber.

[0031] Preferably, the curing system comprises a heating system for heating inner surfaces of the delivery assembly downstream of the spray nozzles and upstream of the distribution channel.

[0032] Conveniently, the air treatment unit comprises at least one optional first exchanger to cool the air, at least one second exchanger to heat the airflow and at least one fan to increase the flow pressure of air entering the delivery assembly.

[0033] In its second aspect, the present invention concerns a method of curing electrodes for lead-acid accumulators by using a drying plant such as the one previously described, the method comprising the following steps of:

[0034] - positioning electric accumulator plates stacked on pallets in a curing chamber;

[0035] - implementing a curing step inside the curing chamber, by subjecting the plates for electric accumulators to be cured to an air flow coming from an air treatment unit in which air is brought to a predetermined temperature and pressure; and

[0036] - collecting the cured plates for electric accumulators at the outlet of the curing chamber.

[0037] Preferably, during the curing step, a water and ozone mixture sprayed upstream of the distribution channel is fed into said flow of air.

[0038] Conveniently, during the curing step, the flow of air is heated upstream of the inflow of aforesaid amount of water and sprayed water and ozone mixture.

[0039] Further characteristics and advantages of the invention can be deduced from the dependent claims and will become clearer in the detailed description of some preferred, but not exclusive, embodiments of a plant and a method of curing electrodes for lead-acid accumulators according to the present invention.

[0040] Brief description of the drawings

[0041] Such description will be set forth hereinafter with reference to the appended drawings provided for indicative, and therefore non-limiting, purpose only, wherein:

[0042] - figure 1 is a schematic perspective view of plant of curing electrodes for lead- acid accumulators according to a preferred embodiment of the present invention;

[0043] - figure 2 is a schematic sectional side view of the distribution channel inside the curing chamber;

[0044] - figure 3a is a schematic sectional view of the curing chamber, with the first and second deflector fins in a first configuration to direct airflow predominantly into the lower half of the curing chamber;

[0045] - figure 3b is a schematic sectional view of the curing chamber, with the first and second deflector fins in a second configuration to direct airflow predominantly into the upper half of the curing chamber;

[0046] - figure 4 is a schematic sectional view of the bell of the delivery assembly; and

[0047] - figure 5 is a schematic view of the spray nozzles.

[0048] Detailed description of embodiments of the invention

[0049] With reference to the figures, a curing plant for curing electrodes for electric accumulators, particularly lead or lead-acid electric accumulators, according to a preferred embodiment of the present invention, is shown therein.

[0050] The curing plant, denoted generally by reference number 100, is suitable for use in a line for curing electrodes for electric accumulators, preferably downstream of a coating machine suitable for coating a paste of active material on the plates, and upstream of a packing machine suitable for stacking the coated plates on each other. The coating machine and the packing machine are of known types and will not be further described herein. The curing plant 100 comprises a curing chamber 3, at least one air treatment unit 2, at least one delivery assembly 4 at least one suction assembly 5.

[0051] The air treatment unit 2 is configured to subject the airflow to at least the following treatments of cooling and de-humidification, where the condensation is recovered and separated from the airflow, heating, to the temperatures specified by the recipe for the product being treated, and increasing pressure, which is achieved through a specific fan 24.

[0052] Possibly, the treatment unit 2 can be configured to implement other processes to the airflow, such as bleeding a portion of the outflow from the drying chamber in order to later make up at more favorable temperature and humidity conditions, i.e., once mixed with the main airflow they bring temperature and humidity to better values for the subsequent treatment.

[0053] For this purpose, the treatment unit 2 comprises at least one first optional exchanger to cool the air, at least one second exchanger to heat the airflow and at least one fan to increase the airflow pressure.

[0054] In the embodiments shown in the figures, the curing plant 100 also comprises a humidity-generating unit and a dehumidification unit for dehumidifying the fed air, which are described in more detail below.

[0055] The curing chamber 3 comprises a box-shaped body comprising insulated lateral walls 3 a in fluid communication with the delivery assembly 4 configured to feed conditioned air into the chamber and a suction assembly 5 in fluid communication with the curing chamber 3 and specifically configured to draw air out The curing chamber 3 extends along a longitudinal extent X-X axis and has a transverse Z-Z axis arranged substantially orthogonally to the longitudinal X-X axis.

[0056] The delivery assembly, as best seen in Figure 5, comprises an inner- distribution unit 6 of air.

[0057] The inner distribution unit 6 of air comprises at least one portion outside the curing chamber 3, typically configured as a bell 17 or otherwise of a divergent shape towards the curing chamber 3, and a distribution channel 7 placed inside the curing chamber 3.

[0058] In the embodiment shown in figures there are three bell-shaped outer portions

[0059] 17.

[0060] Each of the bell-shaped outer portions 17 has walls that deflect air flow within the distribution duct 7 to optimize the air flow entering the curing chamber 3.

[0061] Advantageously, the outer walls of the bell 17 are made of stainless steel and are insulated.

[0062] As best shown in Figure 4, each bell-shaped outer portion 17 may have baffles 18 inside to divide the airflow entering the curing chamber 3.

[0063] Advantageously, to prevent condensation of the water fed into the forced air flow, the outer walls of each bell-shaped outer portion 17, as well as the inner baffles

[0064] 18, can be heated by special electric resistances 20 or steam.

[0065] The bell-shaped outer portions 17 are in fluid communication with the underlying distribution channel 7.

[0066] Preferably, the distribution channel 7 extends, inside the curing chamber 3, in the upper portion thereof for at least 70% of the longitudinal extent of said curing chamber 3. In the embodiment showed in the figures, the distribution channel 7 is constrained to the ceiling of the curing chamber 3, in particular, it is placed at the comer between the lateral wall 3a and the ceiling 3b of the curing chamber 3.

[0067] Preferably, the distribution channel 7 extends across the whole longitudinal extent of the curing chamber 3.

[0068] The distribution channel 7 has at least one inlet for the air coming from the In the embodiment shown in figure 1, there are three air inlets per bell-shaped outer portion 17.

[0069] The inlets are located below the bell-shaped outer portions 17.

[0070] Inside the curing chamber 3, as best shown in Figure 2, the distribution channel 7 has a first converging section 7a and a second straight section 7b placed consecutively below the first converging section 7a.

[0071] The first section 7a is configured to receive air entering the curing chamber 3.

[0072] The second straight section 7b has, at its lower end, the opening 8 and is configured to feed air from first section 7a into the curing chamber 3 through the opening 8, by directing it downwards.

[0073] In the embodiment shown in the figures, the second straight section 7b extends substantially in a vertical direction, that is, parallel to an inner wall 3a of the drying chamber 3.

[0074] The first converging section 7a forms an angle of inclination a between 20° and 50° to the vertical direction.

[0075] In the vertical direction, the second straight section 7b may have an extent greater than the first converging section 7a.

[0076] The opening 8 extends longitudinally across the full extent of the distribution channel 7.

[0077] The opening 8 can have a plan area between 2000 mm2and 200000 mm2.

[0078] In order to properly deliver the airflow in the curing chamber 3, in particular to direct it exactly where it is most needed, depending on the curing process underway, at least a first movable deflector fin 9 may be provided within the curing chamber 3 arranged below the distribution channel 7 and configured to help direct the airflow to the upper or lower portion of the curing chamber 3.

[0079] The first deflector fin 9 has the task of sending a portion of the airflow directly into the upper or lower portion of the curing chamber 3 depending on its position, by increasing the specific airflow rate in that portion of the drying chamber and aiding the drying phase of the electrodes placed therein.

[0080] The first deflector fin 9 extends in the longitudinal direction for at least 70% of the longitudinal extent of the curing chamber 3.

[0081] The first deflector fin 9 extends in the longitudinal direction for the whole longitudinal extent of the curing chamber 3.

[0082] In the embodiment shown in the figures, the first deflector fin 9 extends for the whole longitudinal extent of the curing chamber 3, seamlessly, but it could be formed by shorter side-by-side sections of a first deflector fin 9.

[0083] In order to be movable within the curing chamber 3, the first deflector fin 9 has hinge points at the lower end, i.e., the one closest to the floor of the curing chamber 3 and actuators 11.

[0084] The actuators 11 can be represented by pneumatic or electric piston cylinders, which act in a controlled way by a control unit on the first deflector fin itself.

[0085] The first deflector fin 9 can be tilted with respect to the vertical direction represented by the side wall 3a of the curing chamber 3, so as to form an angle that can vary between 0° and 134°, by varying the tilt of the first deflector fin 9.

[0086] On the wall 3a of the curing chamber 3, below the distribution channel 7, there may be additional first deflector fins 9, quite similar to the one just described but vertically away from it.

[0087] In order to optimize airflow circulation there may be a deflector fin, specifically a second deflector fin 10, on the opposite wall 3a of the curing chamber 3, i.e., the one below the suction opening.

[0088] The second deflector fin 10 is located at the top of the side wall 3a of the curing chamber 3, directly below the air suction opening. The second deflector fin 10 extends in the longitudinal direction for at least 70% of the longitudinal extent of the curing chamber 3.

[0089] Preferably, the second deflector fin 10 extends in the longitudinal direction for the whole longitudinal extent of the curing chamber 3.

[0090] In order to be movable within the curing chamber 3, the second deflector fin 10 also has hinge points at the lower end, i.e., the one closest to the floor of the curing chamber 3 and actuators 12.

[0091] The actuators 12 can be represented by pneumatic or electric piston cylinders, which act in a controlled way by a control unit on the first deflector fin itself.

[0092] Preferably, the first and second deflector fins move simultaneously and controlled by a control unit not shown in the figures.

[0093] As an example, figure 3a shows a schematic sectional view of the curing chamber 3, with the first 9 and second 10 deflector fins in a first configuration to direct airflow predominantly into the lower half of the curing chamber.

[0094] On the other hand, figure 3b shows a schematic sectional view of the curing chamber 3, with the first 9 and second 10 deflector fins in a second configuration to direct airflow predominantly into the upper half of the curing chamber 3.

[0095] In the curing step, it is important to control the humidity level in the air, which must be maintained during the process between 70% and 99% relative humidity, for this purpose there is a system injecting and spraying pressurized water through a plurality of nozzles 22 placed in the air delivery channel downstream of the fan 24 and upstream of the bell-shaped outer portions 17.

[0096] The plurality of nozzles 22 for spraying pressurized water is connected to a pump configured to mix water and gaseous ozone produced by a corona discharge generator (not shown in the figure).

[0097] Advantageously, the use of ozonated water during curing step accelerates the oxidation process of the metal lead present in the active material, thus reducing the process time and producing smaller crystals on the surface of the plates.

[0098] In the following we will describe a generic curing process for lead battery electrodes that begins with the pallets containing the product to be cured from the coating system being placed inside the curing chamber 3, not shown in the figures.

[0099] In the coating system, the plates to be cured are generally sent to a stacking assembly.

[0100] In general, the stacking assembly, also not shown in the figures, is automated and is intended to stack the plates on top of each other, generating stacks of a well- defined number of plates.

[0101] The number of plates per stack can vary depending on various parameters, such as the production volumes per cycle, inner height of the curing chamber and ventilation system, product type, etc.

[0102] The pallets are grouped in groups of two or three or five stacks and are stored inside curing chamber 3.

[0103] In detail, once a pallet is ready for handling, it is loaded by a means intended to move materials and inserted into the curing chamber 3.

[0104] Each pallet stored inside each curing chamber 3 has a precise location that must be respected in order to have proper air circulation inside it. Incorrect positioning may cause imbalances in air circulation inside the curing chamber 3, once the cycle has started on both the incorrectly positioned pallet and on the adjacent pallets. This results in worse distribution of the product quality and / or longer process times.

[0105] Linked to both of these consequences is an aggravation in economic terms.

[0106] A specific program for maintaining controlled temperature and humidity and low forced air circulation is operating during the loading step of the pallets.

[0107] Having placed all pallets inside the curing chamber 3, the curing step can begin. The time duration of a curing step is depending on the type of product to be processed, to which a well-defined recipe corresponds, and on the energy efficiency of the process.

[0108] During the curing step, the air, which is the means used as the energy carrier, is processed in a continuous cycle first through an air treatment unit 2 and then sent and distributed inside the curing chamber 3, through the distribution channel 7. The air inside the treatment units 2 generally undergoes a very specific sequence of processes that may change depending on the point of progress of the curing step itself and depending on what the specific working point specified in the treatment recipe for the product being cured must be. In general, the processes the air is subjected to are the following: optionally cooling, heating to the temperatures specified by the recipe for the product being treated, and increasing pressure, which is achieved through a specific fan. To these processes also others may be added, such as bleeding a portion of the outflow from the curing chamber 3 in order to later make up at more favorable temperature and humidity conditions, i.e., once mixed with the main flow they bring temperature and humidity to better values for the subsequent treatment. The air, once it leaves treatment unit 2, will have the temperature, humidity and pressure values required for that point in the cycle. Temperature and humidity will be exchanged with the treated product in order to cure it, more specifically by giving up heat and removing moisture, whereas pressure energy will be expended through the path that the air will have to take from the delivery assembly 4, through the ducts and the whole drying chamber 3 until it returns to the same starting point, the cycle being closed or semi-closed.

[0109] Typically, in the curing step, the speed of air fed into the curing chamber 3 is lower so as not to result in excessive release of water from the active material that would not allow the oxidation reaction of the metal lead to be completed.

[0110] The air must have, once it reaches the curing chamber 3, not only the correct temperature and humidity values which are specific to the current cycle and also to the state of progress of the cycle itself, but also sufficient kinetic and pressure energy to fit into the passage gaps between each plate stacks on each pallet at each point of the curing chamber 3.

[0111] Thus, it becomes evident how important it is to have an optimal three- dimensional distribution of the flows inside the entire curing chamber 3. More specifically, a better distribution of the airflows directly results in at least two main effects: first, it is given by lower pressure drops that the airflow processed by the fans has to overcome in order to circulate, which thus results in lower energy consumption by the fans; second, it is given by a better distribution of the energy supply brought to the product during the curing cycle at each point of the curing chamber, i.e., from the point of view of the air treatment system, consumption would be lower and cycle times could be reduced, which would be further advantageous from the energy point of view.

[0112] At the curing step, it is equally important to control the humidity level in the air, which must be maintained during the process between 70% and 99% relative humidity. For this purpose, the system uses an injecting and spraying system of pressurized water via the nozzles 22 located in the air delivery assembly, downstream of the fan, that inject a mixture of water and ozone gas. The use of ozonated water during curing step accelerates the oxidation process of the metal lead present in the active material, thus reducing the process time and producing smaller crystals on the surface of the plates.

[0113] In order to prevent the water sprayed by the nozzles from condensing on the surface of the channels of the delivery assembly downstream of the spray, a heating system is provided for the walls and inner baffles 18 of the bells 17.

[0114] Various modifications may be made to the embodiment described in detail, all anyhow remaining within the protection scope of the invention, as defined by the following claims.

Claims

CLAIMS1. Curing plant of electrodes for lead-acid accumulators (100), comprising a curing chamber (3); at least one air treatment unit (2), at least one delivery assembly (4) and at least one suction assembly (5);- said delivery assembly (5) comprising an inner-distribution unit of air fluidically connected to said suction assembly (4) so as to form a circuit for air, characterized in that said inner-distribution unit comprises at least one distribution channel (7) arranged inside the curing chamber (3) in the upper portion thereof and configured for feeding air into the upper portion of the curing chamber (3) and sending at least one portion of the air flow fed into the lower portion of the curing chamber (3);- said suction assembly (5) comprising an opening (14) for suctioning air, arranged in the upper portion of said curing chamber (3);- said distribution channel (7) comprising a first converging section and a second straight section (7b) arranged consecutively to the first converging section (7a), said first section (7a) being configured for receiving the air entering the curing chamber (3); said second straight section being open at the bottom for feeding the air coming from the first section (7a) into the curing chamber (3) by directing it downwards;- said opening (14) for suctioning air being away, in direction of the transverse axis, from said distribution channel (7) so that the flow of air entering from said distribution channel (7) crosses said curing chamber (3) in transverse direction and comes out through said suction assembly (5) once fed into the upper portion of the curing chamber (3) and sent towards the lower portion of the curing chamber (3).

2. Curing plant of electrodes for lead-acid accumulators (100) according to claim 1, characterized in that said curing chamber (3) comprises at least one first deflector fin (9) movable inside the curing chamber (3) arranged below the distribution channel (7) and configured for varying its inclination in order to help direct the flow of air to the upper or lower portion of said curing chamber (3).

3. Curing plant of electrodes for lead-acid accumulators (100) according to claim 1 or 2, characterized in that said curing chamber (3) comprises at least onesecond movable deflector fin (10) arranged below said suction opening (14).

4. Curing plant of electrodes for lead-acid accumulators (100) according to claim 1, characterized in that said humidity-generating unit comprises a plurality of nozzles (22) for spraying pressurized water and feeding it into the delivery assembly upstream of the distribution channel (7).

5. Curing plant of electrodes for lead-acid accumulators (100) according to claim 1, characterized in that said humidity-generating unit comprises a high pressure pump configured for pressurizing the water to be sprayed and mixing it with ozone, and an ozone generator.

6. Curing plant of electrodes for lead-acid accumulators (100) according to any one of the preceding claims, characterized in that said air treatment unit comprises at least one dehumidification system for dehumidifying the air fed into said curing chamber (3).

7. Curing plant of electrodes for lead-acid accumulators (100) according to any one of the preceding claims, characterized by comprising a heating system for heating inner surfaces of the delivery assembly downstream of the spray nozzles (22) and upstream of the distribution channel (7).

8. Curing plant of electrodes for lead-acid accumulators (100) according to any one of the preceding claims, characterized in that said air treatment unit (2) comprises at least one first optional exchanger for cooling the air, at least one second exchanger for heating the flow of air and at least one fan (24) for increasing the pressure of the flow of air entering the delivery assembly.

9. Method of curing electrodes for lead-acid accumulators (100) which uses a curing plant (100) according to any one of the preceding claims, the method comprising the following steps of:- positioning electric accumulator plates stacked on pallets in a curing chamber (3);- implementing a curing step inside the curing chamber (3) by subjecting the plates for electric accumulators to be cured to an air flow coming from an air treatment unit (2) in which air is brought to a predetermined temperature and pressure; and- collecting the cured plates for electric accumulators at the outlet of the curing chamber (3).

10. Method according to claim 9, wherein, during the curing step, a water and ozone mixture sprayed upstream of the distribution channel (7) is fed into said flow of air.

11. Method according to claim 10, wherein, during the curing step, the flow of air is heated upstream of the inflow of said sprayed water and ozone mixture.

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