Small electric-powered pleasure boat

Abstract

Small electric-powered pleasure boat, comprising at least one main electric motor (2), means for storing electrical energy (6, 6', 8), means for generating electrical energy from renewable sources (3, 3', 4), an electrical energy management circuit, and a central control unit (7), wherein the electrical energy storage means comprise at least one Li-ion or similar storage battery (6), characterized in that at least two electrical energy storage batteries (6, 6') are provided, said batteries being housed in respective (106, 106') made of sealed material, preferably steel, each provided with a conduit (116, 116') for introducing water from the outside and a conduit for discharging water to the outside (186, 186') provided with a suitable valve, pump means (126, 126') on each inlet pipe, powered by a battery other than that contained in the respective container, and each battery pack (6, 6') being provided with a set of temperature sensors (156, 156') connected to said central control unit (7), and each container (106, 106') of each battery (6, 6') provided with sensors (176, 176') for detecting the temperature inside the container, the electrical disconnecting contactors (196, 196') also being connected to said central control unit.

Description

[0001] TITLE OF THE INVENTION

[0002] Small electric-powered pleasure boat.

[0003] TEXT OF THE DESCRIPTION

[0004] The present invention relates to boats, and particularly to electrically propelled boats; more particularly, small electric-powered pleasure boats.

[0005] Electric-powered boats are gradually gaining market share, even though their limitations are mainly linked to the fact that their power batteries have a much lower energy density than the fuel used by traditional internal combustion engines. This effectively limits the performance of these vessels, especially in the case of small recreational craft, i.e., those with a hull length of less than 10 meters, which have significantly reduced space and load capacity; cruising speed and range are below the normal expectations of the average user, and the performance-to-cost ratio is typically skewed toward the latter.

[0006] Document WO2022217368 describes an electrically powered vessel in which the battery and propulsion unit assembly is equipped with a cooling system comprising at least one cooling channel isolated from the components to be cooled; advantageously, the cooling system may include heat exchange means, which may be either passive, i.e., based on the movement of the vessel, or active, i.e., equipped with means capable of supplying water to the heat exchange means. However, battery cooling does not provide a different solution for the use of higher capacity and longer life batteries, i.e., Li-ion batteries (function of maintaining the temperature range during normal operation).

[0007] In fact, one problem in small electric boats is related to the safety of the electric energy storage batteries, which, as is sadly well known, can cause fires that are difficult to control. It is almost certain that a small coastal vessel in which a battery catches fire is doomed to sink, requiring the crew to abandon the vessel immediately, as the thermal drift of electric batteries is extremely difficult to control. The aim of this invention is to provide an electrically powered boat in which the batteries are equipped with a fire control safety system that prevents the risk of fire on board caused by the possible self-combustion of the batteries.

[0008] The object of this invention is therefore an electric-powered small pleasure craft comprising at least one main electric motor, means for storing electrical energy comprising at least one Li-ion or similar storage battery, means for generating electrical energy from renewable sources, an electrical energy management circuit, and a central control unit; the boat is equipped with at least two electric energy storage batteries, said batteries being housed in respective sealed containers, preferably made of steel, each equipped with a water inlet pipe, which can be removed from the sea in an emergency, and a water discharge pipe to the outside, with pumping means provided on each pipe, powered by a battery other than that contained in the respective container, and each container being equipped with a set of temperature sensors, installed on the respective batteries, connected to the central control unit.

[0009] In this way, using a special algorithm, the CPU, which continuously monitors all the sensors, is able to detect the onset of a thermal runaway typical of a battery fire. The CPU will then initiate the emergency procedure consisting of:

[0010] - Alarm signal on board indicating “potential battery fire,” with warning to return to port;

[0011] - Automatic disconnection of the power lines of the damaged battery, isolating it from the boat's system;

[0012] - Flooding of the damaged battery compartment by opening the sea drain and activating the water supply pump;

[0013] - Continuous monitoring of the damaged battery temperatures by algorithms processed by the CPU to monitor thermal drift. - Continuous monitoring, via CPU and special temperature sensors installed in the compartment, of the temperature of the battery compartment, with controlled replacement of the compartment flood water via the supply pump (and via automatic opening and closing of the sea drain and supply valves).

[0014] In this way, and with the algorithms stored in non-volatile memory (firmware) and processed by the CPU, the procedure is able to control the internal fire process of the battery (a typical phenomenon of thermal runaway) by acting as a “fire control” or “extinguishing” system.

[0015] In another embodiment, the means of storing electrical energy further include a battery of supercapacitors, also connected to the electrical energy management circuit; the supercapacitors are able to quickly store energy from renewable sources and share it with the electrical energy management circuit.

[0016] The electrical power management circuit includes at least one AC / DC inverter, connected to the central control unit and coupled to the means for generating electrical power from renewable sources, to the means for storing electrical power, to the main electric motor, and also provided with means for drawing power from the ordinary electrical power distribution network.

[0017] In a further variant, an auxiliary stationing motor is provided, controlled by the central control unit by means of a geolocation system such as GPS, which allows the position of the vessel to be managed without the need to drop anchor. This auxiliary engine is located along the longitudinal axis of the boat's keel, in a central position or slightly offset towards the bow and is powered directly by the electrical power management circuit.

[0018] The auxiliary engine, which can rotate on its vertical axis, allows the boat to remain stationary in a predetermined position in protected marine areas where anchoring is prohibited; it also allows safe movement at low speed in the event of main engine failure. The means of generating electricity from renewable sources include photovoltaic cells located on the boat's sun canopy and on at least part of the foredeck of the hull; they may also include micro wind generators located at the bow or on the uprights of the boat's canopy.

[0019] In a further embodiment, the main engine of the boat can be retracted above the waterline, so as to allow navigation, using the auxiliary engine, even in particularly shallow waters, or in the presence of submerged or semi-submerged objects.

[0020] Further advantages and features of the vessel according to the present invention will become apparent from the following detailed description of an embodiment thereof, by way of example and not limitation, with reference to the accompanying drawings, in which:

[0021] Figure 1 is a perspective view of an embodiment of the vessel according to the present invention;

[0022] Figure 2 is a front elevation view of the boat of Figure 1 ;

[0023] Figure 3 is a schematic diagram in plan view from above, showing the interior of the hull of the boat according to the invention; and

[0024] Figure 4 is a schematic block diagram showing the electrical power management circuit of the boat according to the invention.

[0025] Figure 1 shows a perspective view of an embodiment of the boat according to the present invention; 1 designates the hull of the boat, which has a recess 511 on the stem beach 501 in which the foot 102 of the engine 2, equipped with the propeller 202, is arranged. The canopy 301 is supported by uprights 311 , and the photovoltaic panel 3 is arranged on it; similarly, the photovoltaic panel 3' is positioned on the foredeck 401 of the boat. Micro wind generators 4 are located on both uprights 311 .

[0026] Figure 2 shows a front elevation view of the boat of the invention in its stationary configuration; identical parts are marked with the same numbers. The figure shows the presence of the auxiliary engine 5, equipped with rudder 105, and inserted in the protective cage 205 (which allows the crew to swim near the boat).

[0027] Figure 3 shows a schematic top view of the vessel of the present invention; the same parts are indicated by the same numbers. The figure shows the fire safety system involving battery 6' and main battery 6. The two batteries are housed in watertight steel containers 106', 106, which are equipped with pipes 116', 116 for the introduction of water from the outside, each equipped with its own pump 126' and 126, and pipes 186', 186 for draining water to the outside, each of the two pipes being equipped with a suitable valve. The power disconnect switch (196, 196') and the valve assemblies 186, 186' and pump 126, 126' of one battery container are powered by the other battery via the respective fire-resistant cables 166', 166; the two battery packs have their respective sets of temperature sensors 156', 156 positioned on the respective battery, in addition to sensors 176, 176' which monitor the temperature of the water inside each container during an overheating emergency.

[0028] Finally, Figure 4 shows the block diagram illustrating the electrical power management circuit in the boat according to the present invention. The heart of the circuit is the AC / DC inverter 9, to which the storage systems are connected, namely the supercapacitors 8, the main battery 6, and the auxiliary battery 6'; in addition, the main motor 2 is connected to the three-phase AC side of the inverter 9. The energy produced by the photovoltaic cells 3, 3' is fed back to the battery 6 via the AC / DC inverter 103; the supercapacitors 8 are powered in the same way; the connection socket 10 to the ordinary power supply is also connected to the inverter 103. All circuit components are connected to the central control unit 7, equipped with user interface 107, which is also connected to the set of temperature sensors 156, 156', 176, 176' of batteries 6, 6', as is the auxiliary motor 5. Both batteries are connected to the AC / DC inverter with three-phase AC output to the auxiliary motor 5.

[0029] The operation of the boat according to the present invention will be evident from the following. As mentioned in the introduction, the main objective of the research that led to the development of the boat of the invention was to create a small vessel that would have good operational autonomy, be capable of reaching appreciable speeds, and at the same time be safe and reliable.

[0030] When moored in an equipped port, the boat can draw energy from the mains via socket 10 to charge batteries 6, 6' and supercapacitors 8; at the same time, CPU 7 can balance the charging of the accumulators with the energy generated by photovoltaic cells 3, 3' and micro wind generators 4. When leaving the port, the auxiliary engine 5 can be used to support the main engine for maneuvering until the boat is in open water. At this point, only the main engine 2 is operated, in the meantime, the micro wind generators 4 located on the uprights supporting the roof 301 generate energy even at night, when even in the absence of daytime winds, breezes often occur, contributing with the photovoltaic cells 3, 3' (generation during the daytime) to the recharging of the batteries and supercapacitors.

[0031] Once the chosen destination has been reached, the main engine 2 can be switched off and, in the case of a marine protected area, the position of the boat can be controlled using the auxiliary engine 5, which operates in accordance with the geolocation system integrated into the CPU 7. The auxiliary engine 5, as shown in Figure 2, is preferably housed in the keel of the boat, in an opening formed on the longitudinal axis and in particular closer to the bow of the boat itself. Advantageously, the auxiliary engine 5 is protected by a grid dome 205, so that it does not constitute a hazard or come into contact with submerged or semisubmerged objects. The main engine can be raised, especially when in shallow waters or if passengers on board decide to swim near the boat.

[0032] An important aspect that was considered in the development of the boat design according to the present invention is the safety of the electric energy storage batteries. Unfortunately, there have been numerous accidents involving electric land vehicles whose batteries caught fire as a result of sudden overheating (thermal runaway phenomenon). In this case, the main problem is that the occupants of the vessel have no means of escape, and the boat is inevitably doomed to sink in the event of an accident; a battery fire would have a domino effect on the other batteries in the battery pack, creating a thermal shock that would be extremely difficult to control, requiring the crew to abandon ship, with the consequent risks in the absence of collective rescue equipment. To overcome this risk, a safety system has been implemented that requires the presence of at least two 6 and 6' batteries, which are housed in watertight steel containers 106 and 106'. The containers are connected via pipes 116, 116', and 186, 186' to the outside of the vessel so that water can be loaded and unloaded into them in an emergency via special automatically controlled sea inlets in order to control or even extinguish a fire (thermal runaway reaction).

[0033] When the set of sensors 156 or 156' detect abnormal temperature values, controlled by a special algorithm continuously processed by the CPU, in one of the batteries, the disconnect contactor (196, 196') disconnects the faulty battery, the charging pump of the container that triggered the alarm to the CPU 7 is activated, and the inside of the container is flooded. The CPU, processing the specific algorithm, is able to control the abnormal reaction of a battery fire by detecting the sensors installed on the battery, discharging any water inside the container compartment and replenishing it with fresh water. At the same time, CPU 7 suggests navigation at maximum energy efficiency according to weather and sea conditions and programs an emergency return to a safe coastal landing place. Advantageously, the filling and draining pumps of each container are powered by fire-resistant cables, which draw energy from the other battery compartment, so as to ensure operational efficiency in the event of a fire. Since it is highly unlikely that both batteries will catch fire at the same time, this system guarantees passenger safety and, at the same time, allows the boat to be saved as a whole.

[0034] Electricity management is obviously a key aspect of the boat's operation; the optimal balance between generation and consumption is managed by CPU 7, which controls inverter 9; The extensive use of photovoltaic cells on the boat's external surfaces, such as the roof 301 and the bow 401 , allows for constant energy recovery, ensuring the boat's autonomy. Micro wind generators also contribute effectively at night, when even in the absence of daytime winds, breezes often occur.

[0035] The boat, designed in this way, therefore opens up a new scenario in the field of recreational boating, providing a reliable, high-performance, safe, and affordable vessel, which should allow it to be placed in a low market segment with wide distribution.

Claims

CLAIMS1. Small electric-powered pleasure boat, comprising at least one main electric motor (2), means for storing electrical energy (6, 6', 8), means for generating electrical energy from renewable sources (3, 3', 4), an electrical energy management circuit, and a central control unit (7), wherein the electrical energy storage means comprise at least one Li-ion or similar storage battery (6), characterized in that at least two electrical energy storage batteries (6, 6') are provided, said batteries being housed in respective watertight containers (106, 106') made of sealed material, preferably steel, each provided with a conduit (116, 116') for introducing water from the outside and a conduit for discharging water to the outside (186, 186') provided with a suitable valve, pump means (126, 126’) on each inlet pipe, powered by a battery other than that contained in the respective container, and each battery pack (6, 6’) being provided with a set of temperature sensors (156, 156’) connected to said central control unit (7), and each container (106, 106’) of each battery (6, 6') provided with sensors (176, 176') for detecting the temperature inside the container, the electrical disconnecting contactors (196, 196') also being connected to said central control unit.

2. Boat according to claim 1 , wherein said electrical energy storage means comprise at least one supercapacitor battery (8) connected to the electrical energy management circuit.

3. Boat according to claim 1 or 2, wherein the electrical energy management circuit comprises at least one AC / DC inverter (9), connected to said central control unit (7) and coupled to the electrical energy storage means (6, 6', 8) and to the main electric motor (2).

4. Boat according to anyone of the preceding claims 1 to 3, wherein an auxiliary stationing engine (5) is provided, controlled by the central control unit (7) by means of a geolocation system such as GPS (position anchoring with geolocation-assisted servo-assisted engine).

5. Boat according to claim 4, wherein said auxiliary engine (5) is located along the longitudinal axis of the boat's keel, in a position shifted towards the bow.

6. Boat according to anyone of the preceding claims 1 to 5, wherein means for generating electricity from renewable sources comprise photovoltaic cells (3, 3') arranged on the roof of the boat (301 ) and on at least a portion of the foredeck (401 ) of the hull.

7. Boat according to anyone of the preceding claims from 1 to 6, wherein means for generating electricity from renewable sources include micro wind generators (4), arranged at the front or on the uprights of the boat's roof (301 ).

8. Boat according to anyone of the preceding claims from 1 to 7, wherein, by means of a specific algorithm, the central control unit (7), continuously monitoring all the sensors (156, 156'), is able to detect the onset of a thermal runaway typical of a battery fire.

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