Enhancing Safety for Parked Electric Vehicles

Background

In recent years, Singapore has seen multiple battery-associated electrical fire cases that led to tens of thousands of dollars in property damage and loss of human lives. These fire cases affect the livelihood and impact public opinions and acceptance of new battery-related technologies such as Electric Vehicle (EV). As Singapore’s EV adoption journey is still in its nascent stage, we have yet to experience any cases of EV fire. However, globally, multiple EV fire and propagation instances have cascaded, causing mass damages. Hence, it is critical to review and implement relevant mitigation measures to minimise the risk of EV fire.

The common root cause of EV fire happens when damaging the high voltage circuitry or damaged batteries that short, triggering a thermal runaway and igniting. EV fires have similar heat release rates to Internal Combustion Engine (ICE) vehicles.[1] However, EV fires may have a higher rate of occurrences for parked vehicles either by spontaneous ignition or during charging. Statistics from the National Fire Data Centre and US Fire Administration[2] show only ~1% of vehicle fires occurred in parking spaces, including garages. Conversely, report Tesla fire statics shows that ~21% of car fire occurs spontaneously or during charging when the car is parked. For an urban city like Singapore, with high-density multi-storied carparks, underground parking and commercial/industrial parking, the EV fire may pose an additional risk as the propagation of the fire will spread to surrounding property and can cause a cascade effect.

Currently, the sprinkler system is being installed every 12m2 of carparks (except for mechanised car parks). However, there is no existing solutions deployed in Singapore car parks to prevent EV fire propagation. To understand the challenge of EV fire, the National Fire Protection Association (NFPA) reports that fires in electric and hybrid vehicles require both more water and longer extinguishing time than conventional car fires.[3]

[1] P. Sun et al, “A review of battery fires in EV”, Fire Technology, 56, 1361 (2020)]

[2] H. Boehmer et al, Modern Vehicle Hazards in Parking Structures and Vehicle Carriers]

[3] R. Bisschop, O. Willstrand, F. Amon, and M. Rosenggren, ‘Fire Safety of Lithium-Ion Batteries in Road Vehicles’, 2019.

With an expected increase in the likelihood of car park fires, it will be important to look for a cost-effective and high efficacy system that can prevent, reduce, or mitigate EV fires and its damages to properties and potentially injuries or death.

Requirements

  • The technology solution should be retrofittable to urban car parks, including but not limited to multi-storeyed and underground carparks.
  • It should be able to achieve one or more of the following

               (A) Preventing EV fire from starting

               (B) Propagation of fire to neighbouring cars or property

               (C) Extinguishing the started EV fire totally

  • The solution should be automated. It should always be in active use or be potentially triggered in the event of an EV fire, or even before an EV fire.
  • Prevention of fire propagation to adjacent vehicles, objects or property. The electric vehicle should preferably consist of a battery pack of at least 80kWh (est 75th percentile)
  • Solutions should adhere to respective standards and guidelines in environmental safety. This may include “Code of Practice for Fire Precautions in Buildings 2018 (Updated 2022)”, “NEA Environmental Protection and Management Act”, “TR25 Technical Reference for Electric Vehicle Charging System”, and “UL9540A Test Method”, where needed and necessary.  
  • The product should be demonstrated at a prototype phase and provide data or evidence of its efficacy before further potential deployment. The authority can request for witnessing or conduct of such tests by independent laboratory, test institute or government bodies.
  • Multiple potential solutions can be explored. This includes a water-mist sprinkler system that has been proven to be very effective in fighting EV fires, insulation materials, a water-pool system that involves immersion, or a potential smart monitoring system that may prevent even the start or runaway of such fires. Different solutions have their pros and cons. Key factors in deployment may vary in situation, but widespread use will require cost effectivenss, retrofittablity, and ability to demonstrate or ensure effectiveness.

Desired Outcome

  • Existing sprinkler system, avg S$6.85/sqft[1] (USD$5/ sqft ) each lot is 180 sqft = S$1233 per lot. (This cost excludes water storage/pump system and fire detector system that can vary based on the coverage and complexity of the system. (excluding maintenance cost)
  • Cost per lot should be limited to 1 – 1.5 times of existing cost. Est S$1233 to S$1850 per lot. Solutions for other larger lots (e.g. for HGV, buses) may be scaled according to the area.
  • Cost should be reflected as the whole system, from detection to mitigation.

Development Timeframe

The expected development timeframe is as below (subject to changes):

  • Q1-2, 2023: Project awarded, team formation, work preparation
  • Q2-3, 2023: Develop solutions or prototype, with at least lab-based or modelling data
  • Q3-4, 2023: Proof of Concept in at least lab based environment
  • Q4 2023 – Q12024: Proof of efficacy in trials, in controlled, similar or actual environment
  • After Q2 2024: Approval/support from various stakeholders
  • After Q2-3 2024: Availability of solution for deployment

<< Solution should aim to trial by early 2024 and explore mass deployment in 2025 in line with EV adoption trajectory.>>

Additional Info

Potential market / business opportunity for the product/solution:

There are ~1.4M public and private car park lots in Singapore, with the plan to deploy 60,000 charging station by 2030.

Assuming S$1K cost per lot, and 10% of the lots to be fitted with the solution, the value for the industry stands at ~S$6M, up to S$60M by 2030. Assuming 15% provision for all carparks for full electrification, the market potential in Singapore alone may be up to ~S$210M by 2040.

The solution should be relevant to all locations with potential parked vehicles. Private garages, private residential, communal residential, industry, commercial buildings. Such solution is expected to be well sought by building owners, operators or even insurance companies both locally and globally.

Funding Opportunities:

Development funding of up to 70% of qualifying project cost may be provided by EnterpriseSG.

Challenge

Xcite 2022 Innovation Call