The all-electric Mercedes-Benz Vito E-CELL vans have proven their worth in customer use in Berlin and Stuttgart.
The two projects, each with 50 Vito E-CELLs, are intended to run over a period of four years. A total of 230 Vito E-CELL vans, in use in several model regions, have taken to the road as part of the promotional initiatives, with a distance of approximately 650,000 km covered to date.
Mercedes-Benz delivered the first vehicles for field testing to testing partners in Berlin at the beginning of September 2010, and in Stuttgart in January 2011. The areas of application are highly diverse: courier, express and package service providers (KEP, in German: Kurier-, Express- und Paketdienstleister), plant transportation in large corporations, service vehicles for plant maintenance, customer service, and assembly and internal transport within companies. The varied topography was a key factor in the selection of the regions. In contrast to the largely flat terrain of the greater Berlin area, the differences in elevation within the Stuttgart metropolitan area are as much as 350 meters, which presents a real stamina test for the range, recuperation performance and drive properties of the Vito E-CELL.
Intelligent charging technology is used, based on the Smart Charge Communication Unit (SCCU) in the Vito E-CELL. The technology optimises the CO2 balance of the vans with certified green electricity, or even surplus wind energy (“Wind-to-Vehicle/W2V”). The charging technology can also be programmed to lower electricity tariffs to impact operating costs favorably. Where operators use several Vito E-CELL vans, the charging procedures are graded through a process of local charge management (LLM, in German: Lokales Lastmanagement) to ensure that the grid capacity is not overextended.
Range typically not exploited to the full
Initial concerns regarding a too limited range were not substantiated in practice. The vehicles proved capable of covering at least 80 km (50 miles) on a full battery charge, including in winter, which in most cases is a sufficient range. Specifically, this concerns KEP applications with fixed routes, trade companies, supply and municipal companies, and general use within the inner-city environment and within corporate facilities. In a survey conducted during testing in Stuttgart, for example, drivers rated the range of the Vito E-CELL as either good or satisfactory. The fact that the challenging topography of the region fails to limit the on-the-road capabilities of the Vito E-CELL was one of the key findings in field testing.
The charge level of the batteries is a key indicator of range. In Berlin, for instance, this typically fluctuated between 95 and 25 percent of available capacity. This indicates that the maximum range of the Vito E-CELL is seldom fully utilized. Comparatively short charging times of between one and three hours are thus the norm in both regions.
Top speed sufficient, drivers highly motivated
The speed of the Vito E-CELL is electronically limited to 89 km/h to preserve a maximum range. This allows the vans to be driven with ease within the flow of truck traffic on occasional trips on the autobahn. Often, the maximum speed is not reached: in Berlin, for instance, only 30 percent of electric vans were reported to reach top speed on a daily basis. Analyses revealed that, in most cases, the speed of the Vito E-CELL did not exceed 55 km/h (34 mph) in both cities. Speeds were largely in the 15 to 30 km/h (9-19 mph) range.
Technical design of the Vito E-CELL
The Vito E-CELL is based on the mid-length Vito panel van. With a load capacity of up to 900 kg and an unmodified usable load compartment, the Vito E-CELL is suitable for commercial applications without any restrictions. The bodywork as such remains unaffected.
The electric engine, power electronics, converter and AC/DC charger are housed beneath the bonnet. The electric engine develops 60 kW, with a peak torque of 280 Nm. The power is transferred to the front wheels. The high-performance and durable lithium-ion traction batteries are located beneath the load compartment floor. The nominal voltage is 360 V, with a capacity of 36 kWh.
The maximum speed is limited to 89 km/h (55 mph) to maximize the range, which according to NEDC is around 130 km (81 miles). This enables the Vito E-CELL to keep pace with the flow of truck traffic on the autobahn. The vehicle accelerates quickly from 0 to 50/80 km/h (31/50 mph) in just 6.5/11 seconds.
Power supply is via charging stations at fleet depots. The batteries of the Vito E-CELL are charged at a mains voltage of 380/400 V, a process that takes a maximum of six hours. Later, charging will also be possible at a mains voltage of 230 V. Furthermore, the batteries are also charged while the vehicle is under way, through recuperation, in which brake energy is converted into power. Back-up for the Vito E-CELL during the two field tests was provided by the local subsidiaries. Like all Mercedes-Benz vehicles, the Vito E-CELL is also fully integrated into the Star Diagnosis diagnostics system.
Fully fledged safety features, successful crash tests
In contrast to other electric vehicles, the Vito E-CELL is equipped with fully fledged safety features, including ESP. Additionally, the batteries themselves are protected by a crash element. If the airbag is triggered, the high-voltage technology is disabled automatically. The Vito E-CELL has impressively demonstrated its high safety standards in crash tests.
400 Vito E-CELL vans in 2011, further model variants
In 2011, Mercedes-Benz manufactured some 400 Vito E-CELL vans in its Vitoria plant in the Basque region in Spain. There, the Vito E-CELL is manufactured on the same assembly lines as all other Vito vans. This professional standard of manufacturing is a crucial factor for acceptance among commercial customers.
Mercedes-Benz Vans has produced a series of 2000 E-CELL vehicles since 2011. The popularity of the electrically driven van is set to receive a further boost with additional model variants for even greater practice- and customer-oriented purposes. Since the Vito E-CELL has an EU type approval, no monitoring organization assessment is required for licensing within the EU, and special directives for high-voltage technology are also not applicable.
Owing to the high levels of demand and acceptance experienced, it proved possible as early as the testing phase to deploy additional vehicles in other model regions of Germany.
