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CN-121983623-A - Power system based on seawater direct sodium borohydride fuel cell and ship

CN121983623ACN 121983623 ACN121983623 ACN 121983623ACN-121983623-A

Abstract

The invention belongs to the technical field of power generation of seawater fuel cells, and particularly relates to a power system based on a seawater direct sodium borohydride fuel cell and a ship. The device comprises a seawater pretreatment unit, a fuel supply and mixing unit, a direct sodium borohydride fuel cell unit, a power unit and a direct sodium borohydride fuel cell unit, wherein the seawater pretreatment unit is used for receiving seawater and removing impurities in the seawater, the fuel supply and mixing unit is connected with the seawater pretreatment unit and used for mixing NaBH 4 with the seawater to form fuel, the direct sodium borohydride fuel cell unit is connected with the fuel supply and mixing unit and used for converting chemical energy into direct current electric energy through electrochemical reaction of catalytic fuel and the seawater, the power unit is connected with the direct sodium borohydride fuel cell unit and used for converting the direct current electric energy into alternating current and simultaneously providing power for ships and storing electric energy so as to balance power. The invention realizes energy density jump through the direct participation of seawater in the reaction by using an integrated system of seawater pretreatment, fuel supply, electrochemical reaction and power output, and increases the cruising ability and the sailing stability.

Inventors

  • WU XIAOFENG
  • HE YUXIAO
  • WEI YONGSHENG
  • SUN LI
  • YUAN HAO
  • CHEN HAO

Assignees

  • 西北工业大学

Dates

Publication Date
20260505
Application Date
20260407

Claims (8)

  1. 1. A power system based on a seawater direct sodium borohydride fuel cell is characterized by comprising The seawater pretreatment unit comprises a multi-stage filtration unit and a water treatment unit, wherein the multi-stage filtration unit is used for receiving seawater and removing impurities in the seawater to ensure that the concentration of calcium and magnesium ions in the seawater is less than or equal to 0.05mol/L; The fuel supply and mixing unit is connected with the seawater pretreatment unit and is used for mixing NaBH 4 with seawater to form fuel; The direct sodium borohydride fuel cell unit is connected with the fuel supply and mixing unit and converts chemical energy into direct current electric energy through the electrochemical reaction of catalytic fuel, and comprises a plurality of direct sodium borohydride fuel cells which are connected in series, wherein each direct sodium borohydride fuel cell comprises an anode chamber which is arranged in a closed shell and is provided with a positive electrode catalyst, a cathode chamber which is arranged in a corresponding way and is provided with a negative electrode catalyst, and a diaphragm which is arranged between the anode chamber and the cathode chamber, the anode chamber is connected with the fuel supply and mixing unit and is used for oxidizing NaBO 4 to generate NaBO 2 , so that the mass concentration of NaBH 4 in a reaction product of NaBH 4 is less than or equal to 5 wt%, and the cathode chamber is connected with air and is used for carrying out reduction reaction to output direct current; and the power unit is connected with the direct sodium borohydride fuel cell unit, inverts direct-current electric energy into alternating-current electric energy, and is used for providing power for ships and storing electric energy to balance power.
  2. 2. The power system based on the direct sodium borohydride fuel cell of the sea water according to claim 1, wherein the multistage filtering unit comprises a first stage filtering unit, a second stage filtering unit and an ultrafiltration unit which are connected in sequence and are used for removing impurities and harmful ions in the sea water, and the ultrafiltration unit is connected with the fuel supply and mixing unit, so that the concentration of calcium and magnesium ions in the sea is less than or equal to 0.05mol/L.
  3. 3. The power system based on a seawater direct sodium borohydride fuel cell of claim 2, wherein the fuel supply and mixing unit comprises a storage unit for storing NaBH 4 and a mixing unit connected to the mixing unit, the mixing unit connected to the ultrafiltration unit for mixing NaBH 4 with seawater to form a fuel.
  4. 4. A power system based on a seawater direct sodium borohydride fuel cell according to claim 3, wherein the mass concentration of NaBH 4 in the fuel is 15wt.% to 20wt.%.
  5. 5. A power system based on a seawater direct sodium borohydride fuel cell according to claim 3, wherein a flow passage is arranged in the anode chamber, the flow passage is connected with the mixing unit through a liquid injection port, and a liquid discharge port is further arranged in the anode chamber for discharging a reaction product of NaBH 4 .
  6. 6. The power system of claim 5, wherein the cathode chamber is provided with a gas passage, the gas passage being in communication with air via an air inlet, and the cathode chamber is further provided with an exhaust.
  7. 7. The power system based on the seawater direct sodium borohydride fuel cell according to claim 1, wherein the power unit comprises a storage unit, an inverter, a motor and a propeller, the direct sodium borohydride fuel cell unit is respectively connected with the storage unit and the inverter, the storage unit is used for storing and outputting direct current to balance power, the inverter is also connected with the storage unit and the motor, the inverter is used for inverting the direct current into alternating current and providing driving electric energy for the motor, the motor is connected with the propeller, and the motor is used for driving the propeller to rotate and providing power.
  8. 8. A vessel comprising a hull and the power system of any of claims 1-7, the power system being disposed along a central axis of the hull.

Description

Power system based on seawater direct sodium borohydride fuel cell and ship Technical Field The invention belongs to the technical field of power generation of seawater fuel cells, and particularly relates to a power system based on a seawater direct sodium borohydride fuel cell and a ship. Background With the rapid increase of ocean resource development, environment monitoring and security patrol demands, unmanned ships are increasingly widely used as intelligent operation platforms. The common ocean monitoring unmanned ship is provided with a lithium battery pack with the capacity of 60Ah and the working voltage of the lithium battery pack is about 48V by taking a lithium battery, a lead-acid battery and the like as energy storage and power output units. The ship has the endurance time of about 8-12 hours, and the energy conversion efficiency is 85-90%. However, since the energy density of the storage battery is relatively low, such as that of a lithium battery is generally between 100Wh/kg and 260Wh/kg, the performance of the battery gradually declines with the increase of the service time, and the actual endurance capacity of the battery is further reduced, so that the long-time and long-distance offshore operation requirement is difficult to meet. At present, the fuel cell has a core development direction due to high energy density and good environmental protection. The direct sodium borohydride fuel cell has the advantages of high theoretical energy density of 9.3kWh/kg, clean products, such as NaBO 2 and water as reaction products, adopts a traditional sodium borohydride fuel cell system as a power source, releases hydrogen based on hydrolysis reaction of sodium borohydride, generates electric energy by reaction of the hydrogen and oxygen in the fuel cell, is mostly used for inland or offshore small ships, such as 5-10 m monitoring ships, has rated power of 1 kW-5 kW, can continuously travel for 48-60 hours with 50L NaBH 4 solution during constant speed navigation, such as the prior published patent CN117485498A, a foldable unmanned ship for catalyzing sodium borohydride hydrolysis hydrogen generation power source, CN120280515A, a sodium borohydride hydrogen supply fuel cell control system based on dynamic feedback, CN120205035A, a sodium borohydride machine-fuel cell coupling integrated system and the like. Such sodium borohydride fuel cell systems generally consist of a fuel storage tank in which a NaBH 4 solution having a concentration of 10wt.% to 25wt.%, a pure water storage tank, a metering pump, a fuel cell stack, and a DC/DC converter. The metering pump mixes NaBH 4 solution with pure water according to a proportion and then sends the mixed solution into an anode chamber, the mixed solution reacts under the action of a catalyst such as platinum-based material, generated electric energy is converted and then drives a motor, an auxiliary storage battery is used for buffering power fluctuation, equal volumes of even more pure water are needed to be carried, the additional load accounts for 15% -20%, the pure water storage tank leads the actual energy density of the system to be only 25% -30% of a theoretical value, namely less than or equal to 300Wh/kg, the structural complexity of a ship body is increased, the leakage risk exists, the matching performance with the ship body is poor, the space occupation and gravity center deviation risk of the ship body are increased, the power fluctuation reaches 15% -20% under the 3-level sea condition, and the invalid load of the system is excessively limited to the cruising capability and the sailing stability. Disclosure of Invention In order to solve the problems, the invention provides a power system based on a seawater direct sodium borohydride fuel cell and a ship. The invention relates to a seawater pretreatment-fuel supply-electrochemical reaction-power output integrated system, which is used for realizing energy density jump through direct participation of seawater in the reaction and increasing the cruising ability and the cruising stability. The invention solves the technical problems through the following technical proposal. One of the objects of the present invention is to provide a power system based on a seawater direct sodium borohydride fuel cell, comprising: The seawater pretreatment unit comprises a multistage filtration unit, a fuel supply and mixing unit, a direct sodium borohydride fuel cell unit and a direct sodium borohydride power unit, wherein the multistage filtration unit is used for receiving seawater and removing impurities in the seawater to ensure that the concentration of calcium and magnesium ions in the seawater is less than or equal to 0.05mol/L, the fuel supply and mixing unit is connected with the seawater pretreatment unit and used for mixing NaBH 4 and the seawater to form fuel, the direct sodium borohydride fuel cell unit is connected with the fuel supply and mixing unit and used for performing electrochemical reactio