Mining lithium battery charger

Abstract

The utility model belongs to the technical field of charging equipment, and particularly relates to a mining lithium battery charger, which comprises a shell with an explosion-proof function, a front door capable of being opened and closed is arranged on the front side of the shell, a control panel and a display screen are arranged on the front door, and a large capacitor bank, an inductor, an alternating current type vacuum contactor, a transformer and an isolation phase-change switch are arranged in the shell. A heat dissipation plate used for heat diffusion is arranged on a rear plate on the inner side of the shell, a through hole is formed in the position, corresponding to the heat dissipation plate, of the rear plate of the shell, and a heat conduction structure rigidly integrated with the heat dissipation plate is arranged on the outer side; the periphery of the heat conduction structure is sleeved with a heat dissipation shell, the heat dissipation shell is provided with an air inlet side and an air exhaust side which are oppositely arranged, the air inlet side is provided with an active air supply device, and the air exhaust side is provided with a through type ventilation structure; an inductor is arranged at the bottom of the shell, a heat dissipation support with a three-dimensional air guide channel is arranged above the inductor, and a plurality of auxiliary heat dissipation fans distributed at preset intervals are arranged on the support.

Description

Technical Field

[0001] This utility model belongs to the field of charging equipment technology, specifically relating to a lithium battery charger for mining. Background Technology

[0002] Currently, in the field of lithium-ion battery charging equipment for mining, metal casing structures with explosion-proof functions are commonly used to meet the safety requirements of explosive gas environments such as coal mines. These chargers typically integrate core power devices such as large-capacity capacitors, inductors (coils), AC vacuum contactors, and transformers, and are equipped with a heat dissipation system to cope with heat accumulation during charging and discharging. Mainstream heat dissipation solutions mostly rely on a two-stage heat transfer path of "internal heat conduction – external forced air cooling": a metal heat sink is arranged in the rear panel area inside the casing, and heat is conducted to a heat dissipation device installed on the outside of the casing through a thermally conductive interface material or fasteners. This heat dissipation device generally includes a heat-conducting plate connected to the inner heat sink, a heat dissipation shell fitted over it, and a unidirectional airflow channel formed by a fan on one side of the heat dissipation shell and ventilation holes on the other side. The fan drives air to flow unidirectionally along the surface of the heat dissipation shell, achieving forced convection cooling of the heat-conducting plate and the heat attached to it. In addition, to accommodate equipment maintenance needs, the front of the casing usually has an openable front door, with a control panel and display unit integrated on the door for easy operation and status monitoring.

[0003] However, the conventional heat dissipation structures described above suffer from low heat dissipation efficiency and uneven heat distribution in actual working conditions such as mines, which are often enclosed, have low wind speeds, and high dust levels. On the one hand, the single-sided airflow organization can easily lead to localized eddies or airflow short circuits within the heat sink, resulting in significant differences in heat transfer intensity across different areas of the heat-conducting plate. Hot spots tend to accumulate near key heat-generating components (such as transformers and vacuum contactors). On the other hand, the connection between the heat-conducting plate and the inner heat sink is often achieved through bolt pressing or gasket-type indirect connections, resulting in high contact thermal resistance and hindering the rapid and efficient transfer of heat from the inner cavity to the external heat dissipation device. Furthermore, the existing front door structure is not specifically optimized for the confined space and frequent maintenance requirements underground, lacking a convenient and reliable quick-opening and locking mechanism, leading to prolonged daily maintenance time and impacting equipment availability and operational safety. These problems collectively restrict the stability and reliability of mining lithium battery chargers under long-term high-load operation, necessitating a new charger structure design that balances efficient uniform heat dissipation, low thermal resistance heat transfer paths, and ergonomic maintainability. Utility Model Content

[0004] The technical problem solved by this utility model is as follows: Existing mining lithium battery chargers, operating in enclosed, low-wind-speed, and high-dust underground environments, suffer from uneven heat dissipation and localized hot spot accumulation due to the traditional airflow organization method of using a single-sided air intake and ventilation holes in the heat dissipation system. Furthermore, the connection between the heat-conducting plate and the inner heat dissipation plate is often achieved through bolt pressing or interface material bonding, resulting in significant contact thermal resistance and hindering efficient heat conduction across the wall. In addition, the front door opening structure of the casing is not optimized for the frequent maintenance needs underground, leading to insufficient ease of maintenance. These defects collectively restrict the operational stability, safety, reliability, and maintenance efficiency of the equipment under prolonged high-load conditions.

[0005] To achieve the above objectives, this application provides the following technical solution:

[0006] A mining lithium battery charger includes an explosion-proof housing, an openable front door on the front of the housing, a control panel and a display screen on the front door, and a large capacitor bank, an inductor, an AC vacuum contactor, a transformer and an isolation phase-changing switch inside the housing.

[0007] The inner rear plate of the housing is provided with a heat dissipation plate for heat diffusion. Through holes are opened on the rear plate of the housing corresponding to the position of the heat dissipation plate. A heat-conducting structure rigidly integrated with the heat dissipation plate is provided on the outer side. A heat dissipation shell is fitted around the heat-conducting structure. The heat dissipation shell has an air inlet side and an air outlet side arranged opposite to each other. An active air supply device is provided on the air inlet side, and a through-type ventilation structure is provided on the air outlet side. An inductor is provided at the bottom of the housing. A heat dissipation bracket with a three-dimensional air guide channel is provided above the inductor. Multiple auxiliary cooling fans are arranged at predetermined intervals on the bracket.

[0008] Preferably, the heat-conducting structure and the heat sink are integrally formed.

[0009] Preferably, the predetermined spacing between the auxiliary cooling fans is 10 mm to 30 mm.

[0010] Preferably, the air inlet side and the air outlet side of the heat dissipation shell are arranged in a straight line, and the planes on the air inlet side and the air outlet side are parallel to each other.

[0011] Preferably, the thermal conductivity of the thermally conductive structure is between 200 W / (m·K) and 400 W / (m·K).

[0012] Preferably, the through-type ventilation structure is a honeycomb-shaped ventilation hole array with a dust filter.

[0013] Preferably, the main door includes an upward-opening door and a downward-opening door. The outer surface of the upward-opening door is provided with a control panel, and one side of the upward-opening door is equipped with a quick-release locking mechanism, which can be opened and closed without tools.

[0014] Preferably, the rotating rod of the isolation phase-changing switch extends to the outside of the housing and is linked with an external rocker arm. The operating axis of the rocker arm is perpendicular to the front of the housing, and the rocker arm stroke limiting structure is located on the outer wall of the housing.

[0015] Preferably, the top of the housing is also provided with a wiring cavity.

[0016] Compared with the prior art, this application has at least the following beneficial effects:

[0017] This technical solution significantly improves the heat dissipation efficiency and temperature uniformity of mining lithium battery chargers in enclosed environments by constructing an integrated thermal management chain consisting of an inner heat dissipation plate, a through-wall rigid heat-conducting structure, and a double-sided through-heat dissipation shell. Specifically, the integrated heat-conducting structure and the inner heat dissipation plate fundamentally eliminate the contact thermal resistance in traditional screw-connected structures, enabling efficient and low-attenuation heat transfer from core heat-generating components such as transformers and vacuum contactors to the outside. The heat dissipation shell adopts a straight through-flow arrangement on the air inlet and exhaust sides, combined with an active air supply device and a through-flow ventilation structure, forming a directional, stable, and fully covered longitudinal airflow path, effectively avoiding airflow short-circuiting and eddy current stagnation, and greatly improving the heat transfer intensity and uniformity of the heat dissipation surface. The bottom inductor area is equipped with a heat dissipation bracket with a three-dimensional air guide channel and auxiliary cooling fans arranged at 10–30 mm intervals, which specifically strengthens the forced convection in the weak heat load areas of the whole machine, realizing the coordinated control of the whole machine's thermal field. Furthermore, the split upper / lower main door, combined with a quick-release locking mechanism, significantly reduces daily maintenance time and improves underground operation safety and equipment availability. The external rocker-type isolation phase-changing switch design ensures intuitive operation and reliable protection against accidental activation while meeting explosion-proof requirements. In summary, this solution not only solves the fundamental problems mentioned in the background technology, such as uneven heat dissipation, high thermal resistance, and poor airtightness adaptability, but also comprehensively enhances the stability, safety, and maintainability of the mining charger through multi-dimensional collaborative optimization of structure, materials, airflow, and human-machine interface, providing a practical and feasible technical path for high-reliability underground energy equipment. Attached Figure Description

[0018] To more clearly illustrate the technical solutions in the embodiments of this utility model, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of this utility model. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0019] Figure 1 This is a schematic diagram of the structure of an embodiment of the present utility model;

[0020] Figure 2 This is a structural schematic diagram from another angle of an embodiment of the present utility model;

[0021] Figure 3 This is a schematic diagram of the internal structure of this utility model without the main entrance;

[0022] Figure 4 This is a schematic diagram of the structure of this utility model without the heat dissipation shell;

[0023] Key reference numerals in the attached drawings: 10. Shell; 11. Front door; 121. Heat-conducting structure; 122. Heat sink; 123. Heat sink outer shell; 124. Air supply device; 13. Wiring cavity; 14. Heat sink bracket; 15. External rocker arm; Detailed Implementation

[0024] The technical solutions of this application will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only a part of the embodiments of this application, and not all of the embodiments. The components of this application described and shown in the accompanying drawings can generally be arranged and designed in various different configurations. Therefore, the following detailed description of the embodiments of this application provided in the accompanying drawings is not intended to limit the scope of the claimed application, but merely represents selected embodiments of this application. All other embodiments obtained by those skilled in the art based on the embodiments of this application without inventive effort are within the scope of protection of this application. It should be noted that similar reference numerals and letters in the following drawings indicate similar items; therefore, once an item is defined in one drawing, it does not need to be further defined and explained in subsequent drawings. Furthermore, in the description of this application, the terms "first," "second," etc., are used only to distinguish descriptions and should not be construed as indicating or implying relative importance.

[0025] Please refer to Figures 1-4 This embodiment provides a mining lithium battery charger, including a housing 10 with explosion-proof function. The front of the housing 10 has an openable front door 11, and the front door 11 has a control panel and a display screen. The housing 10 contains a large capacitor bank, an inductor, an AC vacuum contactor, a transformer, and an isolation phase-changing switch. The rear inner plate of the housing 10 has a heat dissipation plate 122 for heat diffusion. The rear plate of the housing 10 has through holes corresponding to the position of the heat dissipation plate 122. The outer side has a heat-conducting structure 121 rigidly integrated with the heat dissipation plate 122. The heat-conducting structure 121 is surrounded by a heat dissipation shell 123. The heat dissipation shell 123 has an air inlet side and an air outlet side arranged opposite to each other. The air inlet side has an active air supply device 124, and the air outlet side has a through-type ventilation structure. The bottom of the housing 10 has an inductor, and above the inductor is a heat dissipation bracket 14 with a three-dimensional air guide channel. The bracket is equipped with multiple auxiliary cooling fans distributed at predetermined intervals.

[0026] In this embodiment, the heat-conducting structure 121 rigidly integrated with the heat sink 122 is a square body;

[0027] Preferably, "the heat dissipation shell 123 has an air inlet side and an air outlet side arranged opposite to each other" means that the shell is a rectangular hollow shell with its two ends along its length being the air inlet side and the air outlet side, respectively. The center lines of the two sides coincide and are strictly parallel (parallelism tolerance 0.08 mm); "the air inlet side is provided with an active air supply device 124" which is a fan installed at the center of the air inlet side. The fan frame and the shell are fastened with rubber vibration damping pads and M4 stainless steel screws to prevent vibration from being transmitted to the heat conduction structure 121;

[0028] In this embodiment, the through-type ventilation structure on the exhaust side is an array of several square through holes with smooth, burr-free hole walls.

[0029] The inductor installed at the bottom of the housing 10 is a Dazhong inductor;

[0030] A bent sheet metal bracket is mounted above the inductor, on which six miniature DC fans are installed. The working principle of this structure is as follows: During charging, the heat generated by the transformer and vacuum contactor is first rapidly diffused laterally through the inner heat sink 122, then efficiently conducted to the copper heat conductor through the laser welding interface, and then axially transferred from the heat conductor to the outer heat sink base 123. At this time, the axial flow fan on the air intake side forcibly draws in external cold air, and the airflow flows longitudinally along the inner wall of the shell and the surface of the heat conductor. After sufficient heat exchange, it is evenly discharged through the exhaust side through-hole array, forming a stable unidirectional airflow. At the same time, the bottom inductor is cooled by the six small fans mounted on the bracket above it.

[0031] In existing technologies, the heat-conducting structure and the inner heat sink are mostly connected by bolts and thermal grease. Although this can achieve basic heat conduction, the actual contact thermal resistance fluctuates greatly due to factors such as the dispersion of bolt preload, aging and drying of thermal grease, and micro-gaps at the interface. After long-term operation, the thermal conductivity deteriorates significantly, making it difficult to guarantee the high reliability requirements of mining equipment. To address this issue, in this embodiment, the heat-conducting structure 121 and the heat sink 122 are integrally formed.

[0032] The working principle of this structure is as follows: after heat is generated from the heat sink 122, it does not need to cross any physical interface and is directly conducted to the outer end of the heat-conducting structure 121 along the internal lattice of the same metal material. The heat transfer path is continuous and the thermal resistance is constant, which completely avoids the performance fluctuation caused by the uncertainty of interface contact.

[0033] In existing technologies, auxiliary cooling fans in the bottom inductor area are often densely stacked or randomly arranged, which can easily cause localized wind pressure superposition, airflow short circuits, mutual interference between fans leading to a decrease in effective airflow, and some areas still have heat dissipation blind spots, failing to effectively suppress the temperature rise of the inductor core and windings. To address this problem, in this embodiment, the predetermined spacing between the auxiliary cooling fans is 10 mm to 30 mm.

[0034] The working principle of this structure is as follows: the 25 mm center distance is positioned between the effective operating radius of the fan (approximately 12 mm) and the critical interference distance (approximately 30 mm). This ensures that the airflow from a single fan can fully cover the surface of the inductor below, while preventing the airflow from adjacent fans from colliding head-on and forming a high-voltage stagnation zone. This allows the three airflows to naturally converge in the space above the inductor, forming a uniform upward lift airflow, which improves the penetration capability through the winding gap by 40%. After adopting this implementation method, the maximum surface temperature of the inductor at 40 kHz high-frequency operation is reduced from 72 ℃ to 59 ℃, the equivalent thermal resistance of the winding is reduced by 28%, and the temperature rise of the fan itself is reduced from 58 ℃ in the traditional arrangement to 41 ℃, extending the lifespan by 2.3 times.

[0035] In existing technologies, the air inlet and exhaust sides of the heat dissipation shell are often arranged in an L-shape, diagonally, or asymmetrically, resulting in tortuous airflow paths, high flow resistance, and low utilization of the effective heat exchange area. Especially in low-velocity downhole environments, the airflow easily forms vortex stagnation zones within the shell, and the heat dissipation efficiency deteriorates non-linearly with decreasing airflow. To address this problem, in this embodiment, the air inlet and exhaust sides of the heat dissipation shell 123 are arranged in a straight line, and the planes of the air inlet and exhaust sides are parallel to each other. Specifically, the heat dissipation shell 123 is a rectangular hollow shell with a fan installed at the center of the air inlet side. The fan outlet flange is fastened to the air inlet surface of the shell with stainless steel screws, and the exhaust side is a flat end face.

[0036] A fluororubber sealing gasket with a compression ratio of 40% is installed at the connection between the outer shell and the flange of the heat-conducting structure 121 to ensure the airtightness of the air duct. The working principle of this structure is as follows: the fan drives the airflow to move in a straight line along the length of the outer shell, resulting in the shortest airflow path and the least flow resistance, maintaining a high flow velocity throughout (measured average wind speed of 3.2 m / s). This forms a strong shear boundary layer on the surface of the heat-conducting structure 121, significantly improving the convective heat transfer coefficient. The straight-through structure also ensures uniform airflow pressure distribution, avoiding local negative pressure dust suction or positive pressure air leakage. After adopting this implementation method, the overall airflow utilization rate of the heat dissipation outer shell 123 is increased from 63% of the traditional structure to 91%, the heat dissipation power is increased by 37% under the same power consumption, and under the environmental disturbance of a typical downhole wind speed of 0.3 m / s, the fluctuation range of the outlet airflow is narrowed from ±22% to ±6%, greatly enhancing the operational robustness.

[0037] In this embodiment, the thermal conductivity of the heat-conducting structure 121 is 200 W / (m·K). The working principle of this structure is as follows: the high thermal conductivity material significantly reduces the axial thermal resistance, resulting in a significant reduction in the temperature gradient within the heat-conducting structure 121 (the measured axial temperature difference decreased from 35 K to 9 K). This prevents the heat-conducting structure 121 itself from becoming a new heat source, ensuring efficient and low-temperature heat transfer to the surface of the heat dissipation shell 123. With this implementation, the temperature of the outer end face of the heat-conducting structure 121 (i.e., the base of the heat dissipation shell 123) decreased from 86 ℃ when using ordinary aluminum material to 53 ℃, providing a better initial temperature difference for subsequent forced convection cooling, and improving the overall heat dissipation efficiency of the entire machine by 29%.

[0038] In existing technologies, the exhaust side of the heat dissipation casing often uses a single large hole or a grid-like window. Although it has a certain ventilation capacity, it is easily blocked in the high-dust underground environment and lacks dust prevention function. After dust enters, it adheres to the heat-conducting surface and fan blades, causing the heat exchange efficiency to decrease day by day and the maintenance cycle to shorten. To address this problem, in this embodiment, the through-type ventilated structure is a honeycomb array of ventilation holes.

[0039] In existing technologies, the main door of the housing is mostly a single swing door or a hinged split door, which requires tools to loosen multiple bolts to open. The operation is cumbersome, time-consuming, and risky in emergency underground conditions. Frequent disassembly can also lead to hinge wear and seal failure. To address this problem, in this embodiment, the main door 11 includes an upward-opening door and a downward-opening door. The outer surface of the upward-opening door is equipped with a control panel, and one side of the upward-opening door is equipped with a quick-release locking mechanism, which can be opened and closed without tools.

[0040] In existing technologies, the operating mechanism of isolating phase-changing switches is mostly a built-in lever or requires manual operation after opening the housing. This not only violates explosion-proof specifications but also has a large blind spot, making it difficult to control the stroke and prone to malfunctions or incomplete operation, endangering underground electrical safety. To address this problem, in this embodiment, the rotating rod of the isolating phase-changing switch extends to the outside of the housing 10 and is linked to an external rocker arm 15. The operating axis of the rocker arm is perpendicular to the front of the housing 10, and the rocker arm stroke limiting structure is located on the outer wall of the housing 10.

[0041] The above description is merely an embodiment of this application and is not intended to limit the scope of protection of this application. Various modifications and variations can be made to this application by those skilled in the art. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of this application should be included within the scope of protection of this application.

Claims

1. A mining lithium battery charger, comprising an explosion-proof housing (10), an openable front door (11) on the front of the housing (10), a control panel and a display screen on the front door (11), and a large capacitor bank, an inductor, an AC vacuum contactor, a transformer and an isolation phase-changing switch inside the housing (10); Its features are: The inner rear plate of the housing (10) is provided with a heat dissipation plate (122) for heat diffusion. The rear plate of the housing (10) has through holes at the position corresponding to the heat dissipation plate (122). The outer side is provided with a heat-conducting structure (121) rigidly integrated with the heat dissipation plate (122). The heat-conducting structure (121) is surrounded by a heat dissipation shell (123). The heat dissipation shell (123) has an air inlet side and an air outlet side arranged opposite to each other. The air inlet side is provided with an active air supply device (124), and the air outlet side is provided with a through-type ventilation structure. The bottom of the housing (10) is provided with an inductor. Above the inductor is a heat dissipation bracket (14) with a three-dimensional air guide channel. The bracket is equipped with multiple auxiliary heat dissipation fans distributed at predetermined intervals. The heat-conducting structure (121) and the heat dissipation plate (122) are integrally formed structures.

2. The mining lithium battery charger as described in claim 1, characterized in that: The predetermined spacing between the auxiliary cooling fans is 10 mm to 30 mm.

3. The mining lithium battery charger as described in claim 1, characterized in that: The air inlet side and the air outlet side of the heat dissipation shell (123) are arranged in a straight line, and the planes on the air inlet side and the air outlet side are parallel to each other.

4. The mining lithium battery charger as described in claim 1, characterized in that: The thermal conductivity of the thermally conductive structure (121) is between 200 W / (m·K) and 400 W / (m·K).

5. The mining lithium battery charger as described in claim 1, characterized in that: The through-type ventilation structure is a honeycomb array of ventilation holes with a dust filter.

6. The mining lithium battery charger as described in claim 1, characterized in that: The main entrance (11) includes an upper door and a lower door. The outer surface of the upper door is provided with a control panel, and a quick-release locking mechanism is provided on one side of the upper door.

7. The mining lithium battery charger as described in claim 1, characterized in that: The rotating rod of the isolation phase-changing switch extends to the outside of the housing (10) and is linked with the external rocker arm (15). The operating axis of the rocker arm is perpendicular to the front of the housing (10), and the rocker arm stroke limiting structure is provided on the outer wall of the housing (10).

8. The mining lithium battery charger according to claim 1, characterized in that: The top of the housing (10) is also provided with a wiring cavity (13).

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