Replacement for e-bike batteries: Like Lego, only high-tech - A visit to battery manufacturer Akku Vision

We have an enormous depth of added value," explains Benjamin Hoesel, Production Manager at Akku Vision, "and a lot of manual labour." We are standing in the company's production hall and are surprised: depth of added value in high-end electronics in Germany? What's more, the layman would expect to see high-tech robotic arms here, busily whirring away day and night in deserted rooms. Instead, what we see here in this small hall are men and women wearing ESD equipment, i.e. protective clothing that dissipates electrostatic charge. Among other things, they are inserting battery cells into prefabricated plastic grids. These in turn sit in coloured templates that define both the polarity of the cells and their exact slot. It looks a bit like Lego. Clearly organised, clear and error-free.

However, the history and development of this company seem similarly logical. And are at least as impressive. In 2014, the current Managing Director Daniel Maiberger took over the company E-Bike-Vision, a distributor of replacement batteries. "Maiberger completely reorganised the company," explains Florian Schüssler, Chief Product Officer at Akku Vision, as the main company has been called since 2020. Maiberger quickly focussed on developing his own batteries - instead of buying in imported batteries - and he had a "vision": to develop and produce replacement batteries for common systems here in Germany and become a supplier for e-bike manufacturers. The breakthrough came as early as 2015: batteries with system compatibility for the Bosch Classic Line!

"It was another big step towards the integrated battery," says Schüssler. "A lot of things are different again," explains Erik Bär, Chief Operating Officer and authorised signatory of the company. It starts with the position of the cells and doesn't end with thermal management. Because the development was dynamic and the future looked promising, two investors from Switzerland each took a 14 per cent stake in E-Bike Vision five years ago - with money that appears to have been well invested, as we can see today.

AKKU VISION in facts and figures

• Founded: 2014 (takeover of E-Bike-Vision GmbH) by Daniel Maiberger
• Headquarters: Haibach near Aschaffenburg
• Number of employees: approx. 80
• Production of batteries in 2022: 270,000 batteries
• Annual turnover 2022: 14 million euros
• Internet: akkuvision.de, e-bike-vision.de

We have an enormous vertical range of manufacture here! - Benjamin Hoesel, Production Manager

E-bike batteries: everything from a single source at Akku Vision

In spring 2023, the company has around 80 employees. After several relocations, the company is based in an industrial estate from the 1970s in Haibach in northern Bavaria. Hardly anyone would guess how much high-tech and expertise is hidden behind the typical industrial façade. Development, testing, production, storage and sales are currently carried out here on an area of 5,000 square metres.

The cells are bought in. "Most of our cells are from Samsung, LG, Panasonic, BAK and EVE," says Bär, listing a who's who of global cell production. "We request samples of every new cell on the market and verify their data. The standard for the new 21700 standard today is five ampere hours of capacity, but a new standard with up to 5.8 ampere hours is currently emerging." The manufacturer that wins through with this standard will determine the market. Incidentally, the above-mentioned Li-ion battery standard simply means: 21 millimetres in diameter, 70 millimetres long.

Replacement batteries with higher capacity than the original

Naturally, the major suppliers such as Bosch and Yamaha are the focus of Akku Vision: the high bike sales figures of these companies are also causing an increase in demand for replacement batteries.
"We always develop ourselves, according to our own specifications," says Erik Bär. "Nothing is copied. The aim is always a high-quality product with a higher capacity than the original."

The circuit board of an Intube battery: Due to the trend towards integrating batteries, many changes had to be made to the hardware and software of the power storage units. For example, the battery for the Bosch Active Line system has a whopping 720 watt hours instead of 500. Four design engineers are involved in the mechanical development. Only injection moulded and stamped parts are not produced by Akku Vision itself, nor are the raw circuit boards. As an end consumer, the batteries can only be purchased from specialist retailers - your local e-bike dealer.

He orders for the customer via the E-Bike Vision online shop, which has been the name of the battery business for end consumers since 2020. Any complaints are also handled as normal via dealers. After all, they want the customer to have a competent contact person on site.

Software developed in-house

"The software is the be-all and end-all," emphasises Schüssler. Six specialists work in the development department. Among other things, they take care of the battery management system, which is responsible for the safety of the battery, as well as communication between the motor and battery and traceability. The latter means that all (production) data of the respective product is recorded in a database on the circuit board. They are made available to the specialised trade; the path of the battery and everything that happens in it can therefore be traced. The switch-off values, should the battery become too hot or another problem occur, are also defined by the software. "We also developed this system ourselves at Akku Vision," says Schüssler. After all, it's not just legal standards that have to be complied with. There is also functional safety: after all, nothing should happen if someone short-circuits the battery or connects the wrong charger.

We develop everything ourselves, nothing is copied from the original. - Erik Bär, Chief Operating Officer at Akku Vision

Akku Vision wants to move from replacement battery manufacturer to original equipment manufacturer

Since 2020, however, the company has increasingly focussed internally on the OEM business. The aim is to increasingly produce directly for motor system manufacturers. In other words, customised batteries have been developed for OEM customers since 2020. At a time when sustainability and "Made in Germany" are hugely important, this is certainly a good idea that is being driven forward by a large in-house team.

The Haibach-based company offers two options for system companies. The first: The battery is customised for the customer and completely developed and built by Akku Vision. The second solution is a mix. The design of the housing is customised and developed for the company, while the technical solutions come from Akku Vision's existing portfolio. Akku Vision has been producing an Inframe battery for Oli from Italy since 2022. The company also supplies the energy source for frame integration for Beryl, a large hire bike provider with its own system in the UK.

Building e-bike batteries: Almost like Lego, only in high-tech

In the production department introduced at the beginning, cells are inserted into cell carriers using templates; the cell connectors, i.e. the contact paths between the individual cells, are then connected in a complex welding process. This unit is then married to the battery management system and finally the battery is given its housing with the E-Bike Vision label - provided it is a battery for the end customer. Each individual battery is thoroughly checked at an end-of-line inspection. The line of manual labour described at the beginning is interrupted at one important point: "The supreme discipline," says Production Manager Benjamin Hösel, is the automatic welding of the connectors onto the cells. "This is a huge step forward and an increase in safety," he explains. Manual welding of the connectors, which is still common elsewhere, is nowhere near as accurate as this process. "Sales figures have regularly doubled in recent years," says COO Bär proudly. Of course, the pandemic has also played a major role in the increased interest in e-bikes. In 2022, 270,000 batteries were produced here, but the aim is to reach 1.7 million units by 2025 - by which time significantly more will be automated.

The service department is small; it comprises just three employees and the manager Heiko Proske. The Akku Vision dealers contact him in the event of a service request - i.e. a damaged or defective battery: "We have a return rate of just 0.65 per cent," he explains proudly: "However, the rule is that faulty devices are returned within 72 hours." It's usually quicker." In the department's laboratory, batteries are subjected to electrical stress in a similar way to cycling; measuring devices check all parameters and compare them with target standards - faults are thus quickly found and usually quickly rectified: "If the damage makes a repair uneconomical, we offer a replacement," says Proske. Damaged housings are replaced for 100 euros if the battery is technically in order.

In addition to the regular 24-month warranty, Akku Vision offers its customers a one-year extension for an additional charge. In other words, they are convinced of their product. Understandably, it is very important to the makers of Akku Vision not to be equated with refurbished companies. These companies often only replace defective cells when refurbishing older batteries. How well old and new will then work together and how well the battery management will cope with this remains to be seen. A company that develops complete batteries specifically for large systems clearly stands out from this strategy - also in terms of safety and quality.

What do Bosch & Co. think?

What about the original manufacturer's warranty if the consumer decides to replace their Bosch battery with a Akku-Vision product, for example? "This is not really relevant for our E-Bike Vision brand replacement batteries," explains Akku Vision founder Daniel Maiberger. "Our products are typically used when the customer has been using their e-bike for a long period of time or the original battery no longer offers the desired range. We then provide the customer with a replacement battery with more capacity than the original and therefore also more range."

Akku Vision now also offers products beyond e-bike batteries. A battery testing device for dealers has been developed in Haibach. And the new "Fusione" battery is used in commercial goods vehicles and various micromobiles - an area that the company intends to conquer soon.