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‘Battery monitoring needs to go smoothly for energy storage to enter the mainstream’


A battery software start-up company spun out of one of the largest research groups for energy storage at RWTH Aachen University in Germany recently secured €2.3 million in seed funding to commercialise and expand a platform that aims to take a lot of the “hassle” out of operating energy storage systems.

Dr Kai-Philipp Kairies, a battery scientist and former research programme leader and technical consulting department head at the industry-focused university, is now CEO of ACCURE. The company uses both laboratory and operational data to determine and forecast the health of batteries, allowing customers to analyse and monitor the best ways to use those assets and to gain transparency on how long they will last in the field under a range of usage parameters.

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Dr Kairies spoke to us for our recent tech deep dive into Tesla’s Battery Day and we also took the opportunity to learn more about ACCURE and what it aims to do. From working at the heart of the University at Aachen’s “amazing battery technology ecosystem,” Kairies and his colleagues realised that mobility and energy companies and grid operators alike were “all facing very similar challenges, based on the fact that batteries are pretty complex”.

ACCURE manages more than 200,000 battery modules out in the field, including residential storage for one of Germany’s major providers, E3DC, utility-scale storage systems and electromobility: not just electric cars and their chargers, but also electric ships too. 

What are some of the key challenges that you said your customers are facing, based on the “complexity” of batteries and their operation?

Designing an energy storage system is a very lengthy and difficult process and then operating it the right way – that would be manageable, but most system integrators have at least two, three, or four suppliers of battery modules.

Many of them have had at some point a bad experience with a battery supplier that wouldn’t deliver anymore, they wouldn’t fulfil contracts. What companies are facing now is that they have three or four different suppliers for batteries and they get new generations of batteries every 18 months because everyone is still optimising their systems, and they’re all different, behave slightly differently and they want to have a certain constant quality output and they’re trying their best – but it’s incredibly hard.

What we do is that we take away some of that complexity with highly automated diagnostics and a very scalable data engine that takes all of this battery data, and does some 'battery magic' and as a result gives very actionable insight.

The idea was basically that many many companies can’t afford a team of six or seven battery experts, that you would need to actually understand what’s going on in your product so we automated this whole process of data injection, data cleansing, structuring, analysing and then visualising it.

So the ACCURE software monitors batteries from cell to system level?

It depends on what the customer has – the more detailed the data is, the more we can do with it, so generally we have either cell or module data.

‘Classical big data’

From electric mobility to stationary storage – and even within stationary storage – there are lots of different applications. What are some of the key differences in the way the monitoring strategy might work?

These are a few examples we’re dealing with right now: we have residential storage systems, we have grid-scale utility storage systems, we have EVs, we also have electric ships.

That’s the great thing about it: these are all different batteries, different cells, different form factors, different chemistries and we also have different applications, different temperature levels, different charging curves and such.

So, trying to make sense of that manually would basically be impossible. But we have a pretty huge team of 15 battery experts that really coded all their expert knowledge into this platform which uses battery models and self-learning algorithms and such to take all of these data streams that come in and make them comparable and that way we can benefit from a growing number of assets under management.

It’s classical big data, the more data points you have the better your estimations become. We enable improvements to batteries and to improve battery algorithms across this huge field of battery types and applications. One example would be how can we improve the longevity of home storage systems by slightly changing how they operate.

That’s really cool because many of these companies give 10-year warranties on their products, so they have to make sure they last that 10 years, or it just becomes very pricey for them. So we help these companies in operating these assets that they have in a better way, but also of course taking learnings from these old systems to improve the next generations of systems.

Where are the batteries you are managing at the moment and what sort of scale? What are the main differences between managing the batteries in residential and utility-scale systems?

In terms of the home storage market, it just keeps on growing. Many people expected it to come down, [but] during Corona it even increased. I think that makes a lot of sense because people spent a lot of time at home thinking about what they can do to improve their home: add a solar system and a battery.

[The German market] has surpassed 200,000 systems sold and that’s great and stresses the importance for quality management. With innovators and early adopters, if something is not perfect with a product they might find it interesting. But when you enter the mainstream, the people that buy it and don’t really care about how it works, you need to be at a quality level where things go smoothly.

Currently, most battery installations worldwide, no one exactly knows the state of health of the battery and no one exactly knows how long it’s going to last. We offer this transparency.

It’s pretty much the same in terms of utility-scale storage systems, [but] it’s more about safety. If one particular cell increases or accelerates in running away from its parameters, we can send an early warning and say, disconnect this module.

We have something north of 300MW or 400MW of grid-scale storage in Germany and [a lot of them] are looking for new ways to make money [as primary reserve revenues have plummeted]. They still participate in the frequency response market because making a little bit of money is better than making no money at all, but they are really looking into how they can use their battery, maybe together with a power plant or with a large industrial electricity consumer in a creative way that would increase the value of the asset.

That’s again where we come in because those batteries were designed for frequency control – one single use case – and they have a warranty for this one single use case. If you use your battery in a different way your warranty is not valid anymore.

We look at the operation of the battery in the last few years, make a model of how it can operate under new loads, and then we can give like a cost function of using the battery in new fields. The batteries we manage are mainly in Europe currently, not just Germany but the rest of Europe too – but we are heavily expanding.

Finally, the investors in your latest seed funding round include an early-stage VC, 42CAP and Capnamic Ventures, which focuses on business-to-business tech startups. What can you tell us about those investors and what will their funding help ACCURE to do?

The investors that we got, we had offers from a couple of different investors, we’re super-happy to get the ones onboard we have now because they’re experts in software-as-a-service platforms.

They don’t have this huge deep tech, electricity or even renewable energy background, but they know how to scale a software product. We are already experts in the battery space, we know the market and we know the technology and adding this B2B software expertise into the mix is really important to deliver a good product.

[For example], if you have a customer relationship management (CRM) system, you don’t make that yourself, you buy it, you use an Excel sheet to a certain point – and then when you have too many customers you buy a solution that does it for you. That’s what we want to offer for batteries.

Cover image: ACCURE's COO Dr. Johannes Palmer, CTO Dr. Georg Angenendt and CEO Dr Kai-Philipp Kairies (from L-R). Image: ACCURE.  

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