Twist-lock battery swap electric vehicle

Abstract

The present invention provides a battery pack, battery holder, mobile device, and vehicle body structure that reduces the risk of salt damage to the vehicle body structure and the risk of vehicle fire, further reduces production and operating costs, eliminates the need for a precise and large-scale system when replacing batteries, and reduces the investment required for installing replacement stations. [Solution] To improve the waterproofness of the vehicle body, twist-lock holes are provided at the four upper corners of the replacement battery pack. The twist-lock pins of a spreader equipped with a forklift or crane are fitted into the twist-lock holes of the battery pack to lift the battery pack, bring it into the vehicle body through the open space at the top of the vehicle, and install the battery pack into the battery holder set at the battery pack replacement position. The battery pack replacement position is the hood or rear trunk area where there are no obstacles above the vehicle body, and if the vehicle designer has specified a predetermined position for the battery holder under the seat, a system is provided to move the battery holder into the vehicle.

Description

Technical Field

[0001] The present invention relates to a technology that realizes a vehicle body structure that exhibits high cross-country performance during floods. By performing battery pack replacement from the upper part of the vehicle body, the vehicle body structure becomes more robust and the overall economy is improved.

Background Art

[0002] Electric vehicles were sold in 1891, five years earlier than internal combustion engine vehicles in history, and competed with internal combustion engine vehicles and steam engine vehicles in the market. However, they were driven out of the market by the completion of the mass production system of the Model T Ford of internal combustion engine vehicles in 1908.

[0003] The reason why electric vehicles have come into the spotlight after a long dormant period is partly due to concerns about energy security regarding oil dependence triggered by the oil shock in the 1970s.

[0004] The subsequent popularization and development of electric vehicles are due to the increase in the energy density of the battery, which is the power source that affects the driving range. The batteries adopted have also evolved from lead batteries with low energy density to higher nickel-cadmium batteries, even higher nickel-metal hydride batteries, and recently, the lithium-ion batteries with the highest energy density among them are adopted.

[0005] The advantages of battery swapping include: (1) When purchasing a new vehicle, it is possible to purchase only the vehicle body excluding the battery, enabling the user to reduce the initial cost. (2) There is no waiting time for charging. (3) Since it is前提 that the battery swapping station is within the range of the cruising distance, the peace of mind during driving is improved because the battery is less likely to run out. (4) Maintenance of the battery by the electric vehicle owner himself / herself becomes unnecessary. (5) Additional costs for replacement due to battery degradation do not occur.

[0006] While most electric vehicles use fixed battery systems, the world of radio-controlled cars, which are ahead in electrification, uses almost exclusively replaceable batteries. Therefore, it's only a matter of time before full-fledged electric vehicles also transition to replaceable batteries; it's a natural progression.

[0007] Currently, battery swapping systems in electric vehicles are a minority compared to systems that fix the battery pack to the vehicle body, and the design and manufacture of battery swapping systems are mainly carried out by manufacturers with little experience in the automotive industry. The replacement battery packs in existing passenger cars are mainly located under the seats. During replacement, the entire car is lifted using a specialized lift equipped with a positioning system that includes multiple expensive and precise image processing devices and sensors. The used battery pack is removed through a door on the underside of the car, then a charged battery pack is installed, the door is closed, and finally the car is lowered to the ground to complete the work (see Figures 8, 9, and 10). The conventional method of replacing the battery pack from the bottom of the vehicle body will henceforth be referred to as the bottom replacement method, and the method devised in this invention will be referred to as the top replacement method. [Prior art documents] [Patent Documents]

[0008] [Patent Document 1] Japanese Patent Publication No. 2022-046565 [Patent Document 2] Published Patent No. 2023-523868 [Patent Document 3] JP 2023-528322 Public Review Request [Patent Document 4] JP 2023-522478 Published Patent [Patent Document 5] Patent 6792891 Published Patent [Patent Document 6] Patent 6741323 Published; Patent Application Document 7; Utility Model Application 2025-1820 Filed; Utility Model Application Non-Patent Document

[0009] [Non-Patent Document 1] Nikkan Jidosha Shinbun (Daily Automotive News), "EVs with swappable batteries are spreading in China," Online, May 7, 2023. [Non-Patent Document 2] EV Native [Latest Information on New Chinese EVs] Battery Replacement in 3 Minutes Online June 1, 2023 [Non-Patent Document 3] Yomiuri Shimbun Online: "Completed in 2.5 minutes" - Battery swapping system for commercial EVs (November 4, 2023) [Non-Patent Document 4] Asahi Digital, "Experiencing an EV exchange station on a major street in Guangzhou, China" Online, November 14, 2023. [Overview of the project] [Problems that the invention aims to solve]

[0010] In Japan, linear rainbands have recently occurred frequently, causing flooding in various areas and resulting in numerous submerged vehicles. In western Japan, road flooding due to saltwater from seawater during high tides occurs frequently in coastal areas, and in snowy regions of eastern Japan, large amounts of de-icing agents are spread during the winter, making salt damage countermeasures strongly required for electric vehicles. Neglecting this could increase the risk of vehicle fires due to battery short circuits caused by salt entering from the underside of the vehicle, endangering human lives. In neighboring China and South Korea, electric vehicle fires caused by battery short circuits have become a social problem, and as electric vehicles become more widespread in Japan, this could become a serious social issue involving human lives that cannot be ignored.

[0011] The development of battery swapping systems, which are expected to become mainstream in electric vehicles in the future, is being led by emerging manufacturers in the US and China, such as Tesla, a car manufacturer founded in 2003, NIO, founded in 2014, and CALT, a battery manufacturer founded in 2011. However, all of these manufacturers have a short history in car manufacturing and have only accumulated about 10 or 20 years of know-how. As a result, they are attempting to commercialize products using a bottom-up swapping system, which involves drilling a hole in the bottom of the vehicle body and installing a battery pack swapping gate, and which seems to lack deep consideration for safety and maintainability.

[0012] A vehicle body structure with holes drilled in the bottom offers poor waterproofing and is difficult to protect against salt damage. Furthermore, since typical electric vehicles require a robust underbody structure that can withstand scraping on rough roads and snowy conditions, this type of structure is not something that established car manufacturers in Japan and the US would ever adopt. Adding a gate that provides complete waterproofing to such a fragile underbody structure, and manufacturing an underbody strong enough to withstand strong impacts from rough roads and snowy conditions, would result in soaring costs.

[0013] The bottom-replacement battery pack method requires lifting the electric vehicle on a lift and installing a large, dedicated replacement station equipped with numerous image processing devices, precision sensors, and a CPU-based positioning mechanism. It is estimated that the investment for a single replacement station could exceed 10 million yen, and installing thousands or tens of thousands of these stations would result in a massive investment. Therefore, from an economic standpoint, I predict that this method will inevitably disappear from the market in the future.

[0014] In the current environment of frequent linear rainbands causing road flooding in Japan, there is a high possibility that the connector between the battery and the vehicle body of electric vehicles that use highly flammable lithium-ion batteries, which are boosted to 800V, will be submerged, raising concerns about the risk of vehicle fires. I question whether the Road Transport Vehicle Act's response to vehicles with bottom-replaceable battery packs is sufficient. [Means for solving the problem]

[0015] To achieve high water resistance for the vehicle body, this battery pack is equipped with twist-lock holes at the four corners of the top of the battery pack. The twist-lock pins of a spreader equipped on a forklift or crane are fitted into the twist-lock holes to lift the battery pack, bring it into the vehicle body through the open space on top of the vehicle body, and install the battery pack into the battery holder set at the battery pack replacement position.

[0016] If the replacement position of the battery pack when using the spreader is not at the predetermined position during the operation of the vehicle, for example, when under the seat is the predetermined position of the battery holder, the fixing of the battery holder at the battery pack replacement position is once released, and it is moved by the force of the motor or hydraulic pressure to the predetermined position of the vehicle body until the twist lock hole of the battery holder is fitted with the twist lock pin provided at the predetermined position of the vehicle body, and the fixing of the battery holder is completed.

Effect of the Invention

[0017] Since the replacement of the battery pack of the present invention is performed from the upper part of the vehicle body, compared with the conventional device that performs the replacement from the bottom of the vehicle body, the water resistance of the automobile is increased, and the fire occurrence rate due to the short circuit of the battery is also significantly reduced, so the safety of the vehicle body is greatly improved.

[0018] In the present invention, since an opening and closing door is not required at the bottom of the vehicle body, compared with the conventional replacement system, the strength of the bottom of the vehicle body is significantly increased, and the maintenance cost and manufacturing cost are greatly reduced.

[0019] In the system of the present invention, an expensive and large-scale dedicated replacement device for lifting the vehicle body during battery pack replacement is not required, so it is possible to reduce and suppress the investment amount of the battery replacement station.

Brief Explanation of Drawings

[0020] [Figure 1] It is a top view of the battery pack seen obliquely from above. [Figure 2] It is a three-view drawing of the battery holder, including a plan view from above, a cross-sectional view from the front, and a cross-sectional view from the side. [Figure 3] It is an explanatory drawing of the battery holder movable system. The upper figure is an explanatory drawing when the battery pack is mounted on the battery holder under the bonnet using a spreader and suspended by a crane, and the lower figure is an explanatory drawing of the state where the battery holder with the battery pack mounted is moved to the original fixed position under the seat. [Figure 4]This diagram illustrates a battery holder distribution system where battery holders are installed at two locations on the vehicle body, front and rear. The upper diagram shows the battery pack being attached to the battery holder using a spreader while suspended from a crane, and the lower diagram shows the battery pack installed, with the space above the battery pack serving as a trunk compartment. First, this structure eliminates the need for battery holders under the seats, resulting in a low center of gravity with excellent aerodynamic characteristics and a low ride height. It also eliminates the need for the movable battery holder system defined in claim 3, thus reducing the vehicle's weight and lowering manufacturing and maintenance costs. Furthermore, it easily achieves a 50:50 weight distribution ratio, resulting in neutral steering while the heavy components are located away from the center of gravity, leading to a smooth and ideal steering response without excessive sensitivity to steering inputs. In terms of running costs, having two battery holders allows for battery replacement after one battery is 100% depleted, keeping costs down and improving driving confidence by reducing the likelihood of running out of batteries. In conventional electric vehicles equipped with only one battery pack, replacing the battery when it is 100% depleted is extremely difficult. This increases anxiety when the battery capacity is low, and since the battery is replaced while some capacity remains, it results in an unnecessary financial burden on the consumer. [Figure 5] In the photo of the spreader, the yellow part is the spreader suspended from the crane, and the blue part below it is the container that the spreader is holding and moving. [Figure 6] This is a photo of a red forklift with a spreader attached for use. [Figure 7] In the diagrams illustrating the twist-lock device, the left diagram shows the twist-lock pin in the retracted position, the middle diagram shows the pin extended, and the right diagram shows the pin twisted 90 degrees to the locked position. [Figure 8] This diagram illustrates Tesla's battery swapping system, which is technically a large-scale system consisting of a mechanism to lift the electric vehicle and a mechanism to remove, lower, and move the replacement battery located at the bottom of the vehicle, then move and lift the charged battery and install it in the electric vehicle. [Figure 9]This is a photograph of the exterior of NIO's battery replacement system. [Figure 10] This is a photo of the central part of NIO's battery replacement system. It is equipped with multiple expensive LiDAR sensors and Nvidia image processors to precisely position the vehicle in preparation for battery replacement, and further utilizes NIO's proprietary ADAS (Advanced Driver-Assistance Systems) functions to automate the process. The system is said to cost more than 10 million yen. [Explanation of Symbols]

[0021] 10 battery packs 11 Twist Lock Holes 20 Battery holder body 21 Twist Lock Pin Unit 22 Twist Lock Hole Unit 23 Outer edge of the battery holder opening 24. Outer edge of the bottom of the battery holder 25 Ball caster body 26 balls 30 Spreader 31 Telescopic cylinder body 32 cylinders 33 Hood 34 Storage Units 35 Crane Hook 70 Twist Lock Pin Body 71 Twist Lock Pin

Claims

1. To achieve high water resistance for the vehicle body, this battery pack is equipped with twist-lock holes at the four corners of the top of the battery pack. This allows the battery pack to be lifted by engaging the twist-lock pins of a spreader equipped on a forklift or crane with the twist-lock holes, and then mounted into a battery holder inside the vehicle body through the open space at the top of the vehicle body. Additionally, twist-lock holes are provided at the four corners of the bottom of the battery pack for securing it to the battery holder.

2. The battery holder for housing the battery pack according to claim 1 is equipped with twist lock pins at the four corners of its bottom surface. These pins engage with the twist lock holes of the battery pack housed in the battery holder to secure the battery pack, and twist lock holes are provided inside the twist lock pins on the bottom surface of the battery pack for use in securing it to the vehicle body.

3. Claim 3 is a movable battery holder system in which, if the battery pack replacement position of the battery holder of Claim 2 differs from the predetermined position of the battery holder when the vehicle is in operation, the battery holder is moved between the two positions using the power of a manipulator, winch and drive chain, or by equipping the battery holder itself with drive wheels to make it self-propelled.

4. Claim 4 is a vehicle body structure in which the battery holder, as defined in Claim 2, is installed in two locations: under the hood and in the rear trunk.

Images