Diesel buses converted by e-troFit will be equipped with Voltabox battery system. ZF drivetrains will thus go along with Voltabox technology. More information are becoming official about e-troFit kit for conversion of diesel buses to zero emission ones. A new venture presented during UITP Summit in Stockholm last year.

The presentation was held together with ZF, as the made-in-Friedrichshafen drivetrain is used by e-troFit for the revamping operations. Now Voltabox announced it has concluded a long-term framework contract with e-troFit, based on a cooperation that was started last year, and will therefore supply high-performance battery systems for diesel buses and trucks. The battery system has been developed for e-troFit and can be mounted both at the rear of converted buses as well as on the roof structure.

Voltabox has 8 years of experience in battery development for the public transport market segment. Since 2013, the Group has equipped several hundred trolleybuses worldwide with lithium-ion battery systems. Production sites are located at Voltabox headquarters in Delbrück, Germany; in Austin, Texas, USA, and in Kunshan, China, plus a development site in Markgröningen, Germany.

voltabox e-trofit

Voltabox is e-troFit preferred partner

The first conversions of Mercedes Citaro started in 2019. As a consequence of this new contract, Voltabox revenue volume in this field in 2020 is expected to be in the single-digit million range. Voltabox is now the preferred supplier of battery systems for e-troFit’s conversion solutions for diesel buses. The retrofit solution is being expanded to other widely used bus and truck models as planned, and is also being rapidly marketed in markets beyond Germany.

In the past fiscal year, e-troFit (a subsidiary of Munich-based tech company in-tech) nominated Voltabox AG as the supplier of the battery unit for conversion kits for buses and trucks. At the same time, a team of Voltabox developers designed the battery system, which is precisely tailored to the needs of the conversion solution, in harmony with the drive components and vehicle control electronics, Voltabox explains.

Voltabox battery system developed for e-troFit

The delivery of the first systems took place on schedule in the fourth quarter of 2019. Now that the framework contract has been concluded, the two companies have formally established a long-term cooperation for a continuous supply of lithium-ion battery systems.

Conversion Kit 1, to be distributed in the first step, contains a high-performance and modular Voltabox battery system consisting of modules with prismatic cells based on nickel-manganese-cobalt (NMC) cell chemistry. Distances of up to 260 km can be achieved with one battery charge on this basis, Voltabox points out, and the system can be gradually scaled for longer ranges. The weight-optimized battery system as a whole is designed so that it can be mounted both at the rear of converted buses as well as on the roof structure.

A second life for diesel buses

“Compared to a new purchase, conversion is an extremely economical and sensible alternative based on lower acquisition costs and faster delivery times due to price benefits over time compared to a diesel bus. Instead of continuing to be driven elsewhere as used vehicles, buses originally equipped with conventional combustion engines are given a second life by e-troFit and will be environmentally friendly and locally emission-free in the future, which makes them future-proof for operators,” explains Andreas Hager, CEO of e-troFit GmbH.

In addition to retrofitting, e-troFit also plans to address manufacturers in the future in order to equip new buses, trucks and other commercial and special vehicles.

“The e-troFit approach is both logical and intriguing. Their assembly kit for conversion to an e-powertrain is perfectly adapted, both technically and commercially, and is comprehensively thought out, intensively tested and promises a long-term solution. I am thrilled that Voltabox, with its battery technology and extensive expertise in bus applications, is making an important contribution to sustainability through the modernization of diesel buses in the field. This enables the reduction of emissions in city centers on a broader front,” explains Jürgen Pampel, CEO of Voltabox AG.

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