EV Blueprint seeks to reduce write-offs

Thatcham Research shows it could be economical to repair batteries, keeping EVs over three years old on the road and out of the scrapyard

Safety and crash testing specialist Thatcham Research has developed a strategy to cut the number of electric vehicles being written off by insurers. 

The EV Blueprint sets out to lower insurance costs through cheaper repairs and fewer total losses. The blueprint sets out eight requirements for the automotive industry, designed to ensure battery electric vehicles can be safely assessed, efficiently repaired and economically maintained throughout their lifecycle.

The automotive industry has made progress over the past five years in understanding EVs and implementing essential safety measures in the case of collisions. First responders now have access to clear protocols for managing EVs at road traffic accidents, with comprehensive training available to enable safe isolation of high-voltage systems and management of potential thermal runaway risks. 

Similarly, repair centres across the UK can readily identify electric vehicles and understand the fundamental safety requirements to protect technicians working on high-voltage systems. The industry has gained confidence in handling EVs, and the focus has shifted from basic safety awareness to the need for more efficient recovery, assessment, and repair processes that make economic sense.

However, to achieve increased efficiency, some operational challenges remain. A recent Thatcham Research survey, conducted in partnership with the Centre for Economics and Business Research (CEBR), reveals that battery-related issues remain the primary concern for 44.6% of insurers and 41.7% of repair professionals.

With batteries accounting for up to 40% of a vehicle's total value, even minor collision damage can result in total loss determinations, particularly as vehicles depreciate over time.

Dan Harrowell, principal engineer, advanced technologies Thatcham Research, said: "How affordable it is to insure these cars largely relies on how well the industry can handle repairs after accidents. As repair shops have become more experienced with electric vehicle technology, the costs of fixing these cars have already decreased by 10.7%. 

“To continue making insurance more affordable as more electric vehicles hit the roads, car manufacturers, insurance companies and repairers need to keep collaborating to overcome any remaining challenges. This blueprint provides the roadmap for that collaboration, ensuring we can deliver both the environmental benefits of electrification and the economic sustainability that consumers need.”

The EV Blueprint was developed based on extensive industry consultation and data, including insights from the 2025 CEBR consumer and industry study and research from leading industry bodies. It represents a collaborative effort to establish best practices that will support the UK's transition to electric mobility. 

Thatcham Research's recommendations

The EV Blueprint outlines eight essential recommendations:

1. Resettable emergency safety loop: Emergency safety systems must be designed to be resettable without permanent damage or extensive component replacement, similar to fuel cut-off switches in conventional vehicles.
2. Safe and simplified battery handling: Battery removal and reinstatement processes must be straightforward, avoiding complex procedures or specialised subscription-based tools that create barriers to efficient repairs.
3. Vehicle damage assessment guidelines: Clear, accessible methodologies for assessing battery damage after accidents must be available to all stakeholders, including independent repairers and insurers, to prevent unnecessary total loss determinations.
4. Accessible diagnostics: High-voltage system diagnostics should be standardised and accessible through widely available equipment, comparable to current On-Board Diagnostics systems for conventional vehicles, rather than requiring expensive proprietary tools.
5. Battery damage protection against impacts: Robust under-shields and protective designs are essential to safeguard batteries from underbody impacts and side collisions, with replaceable protective components available at reasonable costs.
6. HV battery repair strategies: Established repair methods for battery casings and mounting brackets must allow completion without removing or disassembling entire battery packs, with pyrotechnic fuses designed for easy reset or replacement.
7. Serviceability of HV batteries: Batteries must be designed for safe disassembly, using modular construction with removable fasteners rather than permanent adhesives, enabling refurbishment and remanufacturing within the UK.
8. HV system component design: Critical components like charge ports should be positioned in less vulnerable locations and designed as standalone units to minimise repair complexity and costs.

Three foundational principles

The recommendations outlined in the EV Blueprint are underpinned by three essential principles:

• Safety: Ensuring protection for everyone who interacts with EVs throughout the vehicle's entire lifecycle, from collision through recovery, assessment and repair
• Sustainability: Enabling a comprehensive circular economy for HV batteries through repair, refurbishment and remanufacture
• Affordability: Ensuring HV components are accessible and reasonably priced, with total loss avoidance strategies that include new parts, warranted refurbished units and remanufactured options

Vision for circular economy

Thatcham Research's EV Blueprint presents a three-year-old EV that has sustained minor side impact damage to the HV battery bracket. Current mandated procedures frequently result in total loss because battery casing damage requires a replacement with a new battery which costs more than the car is worth. For a true circular economy, the battery casing would be repaired without pack removal or replaced with a significantly lower cost refurbished units which would get the car back on the road.

The potential for EV batteries to have a very long operational life has been underlined by a report by Generational, which has tested more than 8,000 electric cars and light commercial vehicles. It found that 8-9-year-old vehicles retain a median 85% battery capacity, compared to new, while the median battery state of health for 4-5-year-old EVs was 93.53%.

“This represents an achievable future state,” said Dan Harrowell. “The vehicle returns to service promptly, the customer retains their vehicle, salvage values improve and environmental impact is substantially reduced compared to manufacturing a new battery. Real-world data is showing that batteries can have a very long usable life that we should try to maximise through sustainable repair.” 

Industry impact

The framework addresses two fundamental challenges: post-collision diagnosis and assessment, and post-collision repair execution. By tackling these issues, the blueprint aims to reduce total loss rates, improve salvage and residual values and ultimately influence insurance premium structures.

The initiative calls on vehicle manufacturers, battery manufacturers, repairers, insurers and training providers to adopt these recommendations, ensuring the electrification transition remains economically sustainable for both industry and consumers.

Jonathan Hewett, chief executive of Thatcham Research, said: “The transition to electric vehicles represents one of the most significant transformations our industry has ever undertaken, but it cannot succeed if EVs become economically unviable to insure and repair. We're seeing too many repairable vehicles written off simply because current designs don't accommodate efficient assessment and repair processes.

“Our Electric Vehicle Blueprint is the result of carrying out real-world EV impact assessments and repair procedures, in-house for more than a decade. These are practical, evidence-based recommendations to overcome three-year-old EVs being written off unnecessarily because of minor battery casing damage. This impacts consumer confidence and, fundamentally, undermines the sustainability credentials that make electrification so important in the first place.

“The eight recommendations we've outlined are entirely achievable. We already see these principles working in conventional vehicles – resettable safety systems, accessible diagnostics, serviceable components. There's no technical reason why EVs can't meet the same standards. What we need now is industry-wide commitment to designing vehicles that can be safely assessed, efficiently repaired, and economically maintained throughout their entire lifecycle.

“We want to work with vehicle and battery manufacturers to create a genuinely sustainable electric vehicle ecosystem. Not just sustainable in terms of emissions, but sustainable economically and practically for the millions of consumers who will depend on these vehicles in the years ahead.”