Thursday, April 11, 2024

The evolution of battery technology and emergency lighting

Andy Davies

Andy Davies, Mackwell’s Commercial Director, looks at the potential for emergency lighting to work in synchronicity with the evolution of battery technology.

Emergency lighting has advanced in recent years, using the most up-to-date battery technology that is suitable for the application. Lithium battery technology has been widely adopted by the industry, which undoubtedly brings a number of benefits. But what future developments could there be for battery technology that is suitable for emergency lighting systems?

To successfully look to the future, it is important to understand the present. In today’s emergency lighting market, lithium iron phosphate (LiFePO4) is recommended. This is because, unlike other lithium-based systems such as lithium-cobalt and lithium-manganese, LiFePO4 is more suited to the standby nature of emergency lighting applications. This technology is less at risk of internal degradation of electrodes and electrode-electrolyte interfaces when used in this way compared to the other lithium chemistries. It is also a safer option due to the lower temperature rise that LiFePO4 experiences should a thermal runaway event occur, although it is important in any case to ensure that your emergency lighting system has a robust thermal management mechanism in place for these rare events.

If developments such as LiFePO4 have been realised and are suitable for emergency lighting, it is not farfetched to see that other technologies could develop in the same way. To see the true benefits, it’s important that the emergency lighting industry gets involved in the development process.

This isn’t with a view to developing technology that is solely for emergency lighting, it is more about collaborating to find batteries that have mass appeal while also being able to withstand the specific requirements of emergency settings. This could be conducted through testing at an earlier stage, including standby applications testing.

Looking to the future of developments, let’s take lithium polymer as an example. This is a thin, lightweight technology that can be curved and manipulated into different shapes and sizes. The flexibility has the potential to be integrated into the fabric of a building, or into new form-factor luminaires.

While this is forward-thinking, the expertise and knowledge across the sector ensures there is capability of incredible developments. There is already a lot of work being undertaken in this area as lithium polymer is not currently developed to its optimum – with relatively short cycle lives, and a poor response to standby usage. For these reasons, whilst the technology is currently unsuitable for emergency lighting, there remains huge potential for improvements in the future.

The need to develop battery technology that will be suitable for future needs is further evidenced through the research and development initiatives that are being undertaken across the UK. Innovate UK, the national innovation agency, is currently supporting a number of projects to develop better materials for lithium-ion batteries, backed by significant levels of funding.

One such project being championed and funded by Innovate UK is the Faraday Battery Challenge. Led by the Faraday Institution, this pioneering work is looking at research and innovation projects, as well as facilities, to drive the growth of a strong battery business in the UK. It aims is to develop batteries that overcome the limitations of existing technologies, such as improved performance, longer-range and faster charging.

The fact that high levels of funding are being awarded to battery-focused R&D projects is indicative of the immaturity of the technology. The good news is, of course, with this financial backing enabling large battery research, development and manufacturing centres, the hopes of developing better batteries stands a strong change of becoming a reality.

Other developments that have the potential to revolutionise the battery market are silicon-based anodes. This technology is supporting the development of better batteries, and in time will deliver great results. Electric vehicles will have better range, while consumer electronics will see further innovations thanks to better performance and convenience. Ultimately, using silicon in place of carbon delivers improved performance, higher energy density and a cost reduction.

Sustainability is going to become increasingly important in the future too. While lithium technology is already recyclable, the infrastructure to support this remains under-developed. It is positive that there is funding available to improve these processes, making them more readily available at scale.

All of these innovations have the potential to come together to deliver a lightweight, high-density battery that is easily recyclable and available in a plethora of shapes and sizes. This is a very exciting prospect.

As an industry, the emergency lighting sector needs to be poised to take advantage of the wealth of possibilities as battery technology evolves. Emergency lighting systems can undoubtedly benefit from this improved technology, but the involvement at the development stage from manufacturers and sector specialists is somewhat lacking. By seeking opportunities to engage in research, testing and development, the emergency lighting sector can be an integral player in the emergence of improved battery technology, not an afterthought.

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