Modular battery system for an electric boat

Abstract

The present invention relates to a boat (1) comprising: • a shell (10); • a casing (12) in which a plurality of racks (14) are arranged; • a plurality of extractable batteries (16) adapted to be plugged into the racks (14) of the casing (12); • a control module (18) configured to control the power supplied to items of electrical equipment (20) on the boat (1) from the batteries (16); the batteries (16) of the plurality of batteries (16) being controlled to supply power to the items of electrical equipment (20) sequentially, one after the other, or in combination, several batteries (16) simultaneously supplying power according to a selectable operating mode from among an economical operating mode, a manoeuvring operating mode and a supercharged operating mode.

Description

Modular battery system for electric boat

[0001] The present invention relates to the field of electric or hybrid propulsion boats and more particularly aims at a modular battery system. STATE OF THE ART

[0002] As with all resources on board a means of naval transport for people or goods, the energy on board a boat presents significant constraints on its management on board, whether for all the systems contributing to the navigation or safety of the boat, or for the systems intended for passenger comfort. It is thus known to power electrical equipment by a set of on-board batteries.

[0003] It is also common, on the other hand, in the case of a sailing boat, to compensate for the intermittent propulsion provided by the force of the wind by a secondary mechanical propulsion using an engine, by transforming stored energy on board in the form of fuel or a battery. The engine of a sailboat is also generally used for maneuvers in a port or for anchoring at anchor.

[0004] It is known for hybrid electric sailboats to combine the electric motor and the battery system intended to power the boat's electrical equipment. The batteries then provide electrical energy simultaneously to an electric motor to ensure the boat's propulsion, but also to all the electrical equipment. It is thus known to use as an electric motor a reversible electric machine configured to recharge the battery pack by driving the propulsion propeller, during navigation phases where the sailboat is propelled by the force of the wind. The electric motor is then in so-called "hydro-generator" operation.

[0005] Despite the possibility of recharging the battery pack by a hydro-generator, wind propulsion is inherently intermittent and there is a significant risk of the battery pack being discharged in the absence of wind powerful enough to support propulsion. If this situation continues for a long time, it may require external assistance for the boat. A similar situation can occur for a boat powered solely by electricity.

[0006] To overcome this drawback, it is desirable to increase the capacity of the batteries carried on the boat, which inevitably leads to an increase in the mass and especially the volume occupied by all the batteries, the size already being a limiting parameter when designing a vessel.

[0007] Furthermore, the useful power supplied by the battery pack is, in the state of the art, almost constant and not controllable, which means that there is no possible prioritization for the skipper of a boat between the allocation of electrical power to functions essential to navigation and to mainly comfort functions, for example for passengers.

[0008] Finally, battery charging operations, particularly when moored in a port, require an electrical infrastructure for connection to the network close to the boat, which limits the possible stopping places for an electrical energy supply, for example during a long delivery trip.

[0009] The invention thus aims to remedy, at least in part, these drawbacks of the state of the art. PRESENTATION OF THE INVENTION

[0010] More specifically, the invention relates to the installation of removable batteries, in particular by proposing a boat comprising: a hull; a box in which a plurality of racks are arranged; a plurality of removable batteries adapted to be connected to the racks of the box; a control module configured to control the power supply of electrical equipment of the boat from the batteries; the batteries of the plurality of batteries being controlled to supply energy to the electrical equipment sequentially, one after the other, or in a combined manner, several batteries supplying energy simultaneously, according to an operating mode selectable from among an economic operating mode, a maneuvering operating mode and a supercharged operating mode.

[0011] The boat further comprises a keel located under the hull, the box being waterproof and contained in the keel, the racks being vertical and extending into a volume of the keel. The boat further comprises a retractable hatch allowing access to the waterproof box from inside the boat, the batteries of the plurality of batteries being elongated and adapted to be connected to the racks of the waterproof box.

[0012] Thanks to such a combination of characteristics, such a plurality of batteries allows a user to replace a battery, for example a discharged one with a charged one, or a defective battery with a functional one. Thus, it is possible to charge all the batteries remotely from the boat, which expands the possible locations for refueling during a delivery. In addition, such a control module makes it possible to control the electrical power supplied by the plurality of batteries, depending on the operating mode chosen and the current charge of the batteries.

[0013] In such a configuration, the plurality of batteries and the racks participate in the stabilization of the boat by contributing to the ballast of the keel, in the part also called keel fin particularly in the case of a monohull boat such as a sailboat, making it possible to lower the center of gravity of said sailboat to increase its stiffness to the canvas. In addition, when the batteries are arranged in the volume delimited by the submerged parts of the boat, designated "live works", a thermal flow circulates between the batteries and the water through the live works of the boat, to cool the batteries and guarantee operation in optimal conditions.

[0014] In the economical operating mode, the electrical power is mainly supplied sequentially, battery after battery. The control module also prioritizes the allocation of power to the electrical equipment essential for navigation, including at least the electric motor in the case of an electrically powered boat, for example, and guaranteeing the supply of electrical energy to the instruments for measuring navigation conditions, such as a GPS receiver, or to communication instruments such as a very high frequency radio transponder.

[0015] In the maneuvering mode of operation, electrical power is supplied sequentially, battery by battery, or in combination, depending on the mechanical power that the electric motor must develop, for example during an emergency maneuver, to develop a significant mechanical torque to avoid an obstacle. Essential electrical equipment is also powered in the maneuvering mode of operation.

[0016] In the supercharged operating mode, the electrical power is in particular mainly supplied in a combined manner by several batteries of the plurality of batteries, to power, in addition to the electric motor and essential electrical equipment, non-essential electrical equipment mainly for the comfort of passengers, for example an electric resistance of a thermodynamic water heater.

[0017] The selection of an operating mode by a user allows for maximum matching of electrical energy consumption to the need for a given use. In addition, the removable batteries can, in the three operating modes, temporarily operate each in an enhanced regime, i.e. a regime in which each battery can temporarily provide power greater than its nominal power.

[0018] Furthermore, such removable batteries can be removed when no crew member is on board the vessel, thus preventing attempted theft using the boat's engine. The batteries are preferably removable manually and without tools.

[0019] Advantageously, all of the batteries in the plurality of batteries are identical. In such a configuration, each battery can be interchanged indiscriminately, and the entire electrical network of the boat adopts the same behavior in a sequenced battery usage mode. Preferably, the plurality of batteries comprises at least 4 batteries, each battery having a storage capacity preferably between 0.5 kWh and 3 kWh. Each battery preferably weighs between 7.5 kg and 20 kg, so that it can be extracted and transported by a single user.

[0020] Advantageously, the batteries are elongated and arranged longitudinally in the racks. In such a configuration, the box is accessible from inside the boat, for example in a hold of the boat. The batteries are then extracted from the racks by a horizontal longitudinal movement. The box can advantageously be positioned according to various arrangements of the hold of the boat, so as to, for example, further ballast the bow or stern of the boat and modify the longitudinal angle of trim of the boat.

[0021] Advantageously, the boat includes a selector for switching to the next battery when a battery is discharged. Thus, during sequential use of the batteries, the operation of switching from a charged battery to a discharged battery is carried out without interruption of the power supply to the electrical equipment for the same given operating mode.

[0022] Advantageously, the selector is manual or automatic. Preferably, the selector is located near the helm station, so that the boat's helmsman can manually select the battery(ies) available, as well as decide which operating mode to engage.

[0023] Advantageously, the boat includes a visual indicator of the charge level of the battery(ies) in use.

[0024] Advantageously, the boat includes a level indicator for each of the batteries.

[0025] Advantageously, the boat includes at least one reserve battery.

[0026] Advantageously, the electrical equipment comprises at least one electric motor. In such a configuration, the motor rotates a propeller to generate thrust propelling the boat. In particular, the motor and the propeller can be contained within the volume of the keel.

[0027] Advantageously, the electric motor is reversible to operate as a generator. In such a configuration, the generator transforms mechanical energy from the rotation of the propeller into electrical energy to charge the plurality of batteries, in particular during a sailing phase of a sailboat. The batteries then have an additional operating mode called the recharging operating mode.

[0028] According to another aspect of the invention, it relates to a method of using a boat as described above, comprising determining by a user an operating mode selectable from an economy operating mode, a maneuvering operating mode and a supercharged operating mode; the method further comprising powering electrical equipment from a plurality of batteries sequentially, one after the other, or in combination depending on the selected operating mode.

[0029] Of course, in addition to the removable batteries, as briefly described above, the boat may include batteries not configured to be removable. In this case, only a portion of the batteries installed on the boat are configured to be removable and to be recharged after being transported outside the boat. PRESENTATION OF FIGURES

[0030] The invention will be better understood on reading the following description, given solely by way of example, and referring to the appended drawings given as non-limiting examples, in which identical references are given to similar objects and in which:

[0031] This is a schematic representation of a boat according to a first embodiment of the invention.

[0032] This is a schematic representation in isometric perspective of a boat keel according to the same embodiment.

[0033] It should be noted that the figures set out the invention in detail to enable the invention to be implemented; although not limiting, said figures serve in particular to better define the invention where appropriate. DETAILED DESCRIPTION OF THE INVENTION

[0034] In Figures 1 and 2 a boat 1 is illustrated according to one embodiment of the invention. The boat 1 is here a monohull sailboat, but can alternatively be a motorboat such as a yacht or a speedboat.

[0035] The boat 1 comprises a hull 10 configured to ensure the buoyancy of the boat 1 and the external walls of which are in contact with water. The hull 10 delimits an interior volume of the boat 1 comprising a hold accessible from the deck of the boat 1 and a keel 22 accessible from the hold. In the case of a motor boat, the keel 22 designates the lowest axial part of the hull 10. Here, the keel 22 projects axially under the hull 22 and has a general fin shape. The keel 22 delimits an interior volume accessible from the hold by a retractable hatch 24.

[0036] In the embodiment shown, the interior volume of the keel 22 contains a sealed box 12, in which extend vertical racks 14 on which are connected a plurality of batteries 16 extractable from the racks 14. The batteries 16 are preferably elongated prismatic parallelepipeds, that is to say that the height of a battery 16 is significantly greater with respect to the dimensions of a base section of said battery 16. The batteries 16 are all identical. And their placement in the racks 14 is undifferentiated. The electrical network thus adopts the same behavior in a sequenced mode of use of the batteries 16. Each battery 16 preferably has a storage capacity of between 0.5 kWh and 3 kWh. Each battery 16 preferably weighs between 7.5 kg and 20 kg, so that it can be extracted and transported by a single user.Such removable batteries 16 can be removed when no crew member is on board the vessel, which prevents attempted theft by damaging the boat's engine. The manually removable batteries 16, without tools, are disconnected from the racks when the physical contact between a battery 16 and its associated rack 14 is broken. The box 12 further comprises reserve batteries 28 disconnected from the racks 14 for emergency replacement, for example in the event of a malfunction observed by a battery 16 during a delivery. Also, it is possible to charge all of the batteries remotely from the boat, which expands the possible locations for refueling during a delivery.

[0037] The plurality of batteries 16 is controlled by a control module 18 to power electrical equipment 20 of the boat 1. The control module 18 is located in the box 12, in the immediate vicinity of the racks 14.

[0038] The batteries 16 are controlled to supply energy to the electrical equipment 20 sequentially, one after the other, or in combination, several batteries 16 supplying energy simultaneously, according to an operating mode selectable from an economic operating mode, a maneuvering operating mode and a supercharged operating mode.

[0039] In the economical operating mode, the electrical power is notably supplied battery 16 by battery 16 sequentially. The control module 18 further prioritizes the allocation of power to the electrical equipment 20 essential for navigation, including at least one electric motor for driving a propeller 26 in the case of an electrically powered boat, and guaranteeing the supply of electrical energy to the instruments for measuring navigation conditions such as a GPS receiver or communication instruments such as a very high frequency radio transponder.

[0040] In the maneuvering operating mode, the electrical power is supplied in particular battery 16 by battery 16 sequentially or in combination, depending on the mechanical power that the electric motor 20 must develop, for example during an emergency maneuver, to develop a significant mechanical torque to avoid an obstacle. The essential electrical equipment is also supplied in the maneuvering operating mode.

[0041] In the supercharged operating mode, the electrical power is mainly provided in a combined manner by the plurality of batteries 16, to power, in addition to the electric motor 20 and the essential electrical equipment, non-essential electrical equipment (not shown) mainly for the comfort of the passengers, for example an electric resistance of a thermodynamic water heater.

[0042] By being arranged in the volume delimited by the submerged parts of the boat, designated “live works”, a thermal flow circulates between the batteries 16 and the water through the live works of the boat, to cool the batteries 16 and guarantee operation in optimal conditions.

[0043] In the embodiment described, the plurality of batteries 16 and the racks 14 participate in the stabilization of the boat 1 by serving as ballast in the keel, also called a centerboard particularly in the case of a monohull boat such as a sailboat, by lowering the center of gravity of the boat 1 to increase its stiffness to the canvas. By stiffness to the canvas, we mean the vertical distance separating the barycenter of the points of application of the forces exerted by winds on each of the sails, designated sail center, from the barycenter of the points of application of the forces due to the water pressure on the underwater works of the boat 1 and the forces generated by the movement of the boat 1 in the water due to the underwater works behaving like a profile in a fluid flow.

[0044] The control module 18 is connected to a selector (not shown), preferably located near a helm station of the boat, so that the helmsman of the boat can manually select the battery or batteries available, as well as decide which operating mode to engage. The selector switches by default to a charged battery 16, at least partially, when one of the batteries currently in use falls below a critical discharge threshold, for example 3% of its nominal capacity. The control module 18 ensures combined use of the batteries 16, even transient within a sequential use, so as to guarantee the continuity of the supply of electrical energy to the electrical equipment 20. The control module 18 is also connected to a level indicator (not shown) for each of the batteries 16, the level indicator being visible to the helmsman of the boat 1 from the helm station.

[0045] It will also be noted that the invention is not limited to the embodiments described above. It will indeed appear to those skilled in the art that various modifications can be made to the embodiment described above, in light of the teaching which has just been disclosed to them.

[0046] For example, the electric motor 20 is reversible to operate as a generator. In such a configuration, the generator 20 transforms mechanical energy from the rotation of the propeller 26 during the movement of the boat 1 into electrical energy to charge the plurality of batteries 16, in particular during a sailing phase. The batteries 16 then have an additional operating mode, designated the recharging operating mode.

[0047] According to another embodiment (not shown), the batteries 16 are elongated and arranged longitudinally in the racks 14 of the caisson 12. In such a configuration, the caisson 12 is arranged directly in the hold of the boat 1. The batteries 16 are then extracted from the racks 14 by a horizontal longitudinal displacement. The caisson 12 can be positioned according to various arrangements of the hold of the boat 1, so as to ballast for example the bow or the stern of the boat 1 more, or so as to modify the longitudinal trim angle of the boat. By positioning for example the caisson 12 towards the stern of the boat 1, the vertical distance between the waterline and the lowest point of the hull at the stern, designated aft draft, is greater than the vertical distance between the waterline and the lowest point of the hull at the bow, designated forward draft.In this configuration, the longitudinal trim angle of the boat is increased, which notably improves its maneuverability as well as its seakeeping, for example in adverse weather conditions.

[0048] In the detailed presentation of the invention given above, the terms used should not be interpreted as limiting the invention to the embodiment set forth in the present description, but should be interpreted to include all equivalents the prediction of which is within the reach of those skilled in the art by applying their general knowledge to the implementation of the teaching just disclosed to them.

Claims

Boat (1) comprising: a hull (10); a box (12) in which a plurality of racks (14) are arranged; a plurality of removable batteries (16) adapted to be plugged into the racks (14) of the box (12); a control module (18) configured to control the power supply of electrical equipment (20) of the boat (1) from the batteries (16);the batteries (16) of the plurality of batteries (16) being controlled to supply power to the electrical equipment (20) sequentially, one after the other, or in combination, several batteries (16) supplying power simultaneously, according to an operating mode selectable from an economical operating mode, a maneuvering operating mode and a supercharged operating mode, the boat further comprising a keel (22) located under the hull (10), the box (12) being waterproof and contained in the keel (22), the racks (14) being vertical and extending into a volume of the keel (22), the boat (1) further comprising a retractable hatch (24) allowing access to the waterproof box (12) from the interior of the boat (1), the batteries (16) of the plurality of batteries (16) being elongated and adapted to be connected in the racks (14) of the waterproof box (12).; The boat (1) of claim 1, wherein all of the batteries (16) of the plurality of batteries (16) are identical. Boat (14) according to one of claims 1 to 2, in which the batteries (16) are elongated and arranged longitudinally in the racks (14). Boat (1) according to any one of the preceding claims, comprising a selector for switching to the next battery (16) when a battery (16) is discharged. Boat (1) according to the preceding claim, the selector being manual or automatic. Boat (1) according to any one of the preceding claims, comprising a visual indicator of the charge level of the battery(ies) (16) in use. Boat (1) according to any one of the preceding claims, comprising a level indicator for each of the batteries (16). Boat (1) according to any one of the preceding claims comprising at least one reserve battery (28). Boat (1) according to any one of the preceding claims, wherein the electrical equipment (20) comprises at least one electric motor. A method of using a boat (1) according to any preceding claim, comprising determining by a user an operating mode selectable from an economy operating mode, a maneuvering operating mode and a supercharged operating mode; the method further comprising powering electrical equipment (20) from a plurality of batteries (16) sequentially, one after the other, or in combination depending on the selected operating mode.

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