The Mobile Energy Vault (MEV) is designed to extract energy from an existing reservoir electrical connection and store it initially in reused vehicle batteries. During charging, this energy can be delivered at significantly higher power levels. According to media reports, Alye is primarily targeting fleet locations where available grid connection capacity is insufficient for conventional fast charging.
At launch, two variants are planned. The MEV200 offers 155 kWh of storage capacity, while the MEV300 offers 232 kWh. Both systems are capable of charging two vehicles simultaneously. Allye specifies a maximum DC charging power of up to 400 kW.
The technical basis is the 800-volt architecture of the Max300 mobile battery storage system. According to the manufacturer, it supports 400 and 800 volt vehicle systems. The technology called PackFlex allows the operation of battery packs of different sizes, ages and cell chemistries within a single system.
Allye says it uses entire battery packs from decommissioned electric vehicles, rather than newly produced cells. Per unit, this approach is estimated to save approximately 15 to 24 tons of CO₂ equivalents compared to a system using new batteries. This figure is based on the manufacturer’s calculations.
Battery Storage Buffers Weak Grid Connections
The approach involves decoupling grid power and load power. The battery system can be charged for a long period with relatively low power from the grid and then deliver this energy to the vehicles at high power for short periods.
A practical example of this approach is a project by the J&M Murdoch company in Glasgow. According to Allye, a network upgrade for a waste management company’s operational depot was quoted at approximately £300,000. Instead, Allye and charging provider Chargepoly installed a Max300 unit on an existing 32A connection with 22kW of capacity. The storage system now powers a standalone DC fast charger for two electric vehicles, providing around 200 kWh of energy per day, the company claims.
This example also highlights the limitations of the concept. While a battery storage system can enable high charging power despite a weak grid connection, it does not replace the volume of energy required. The number of vehicles that can be serviced daily still depends on how much electricity can be recharged via the existing connection over several hours.
Allye maintains that this solution helps avoid long wait times for new network connections. The company expects lead times of 18 to 36 months for new depot connections in the UK. In contrast, the MEV can be installed using industrial sockets or a fixed connection and put into operation within a few hours. The system can also be dismantled and redeployed to another warehouse in the event of a change in location.
For its operation, Allye incorporates additional security elements. The charging cables are equipped with cut monitoring, forensic markings and quick release mechanisms to facilitate faster replacement of damaged cables. Cameras monitor charging stations and cables. Functions such as pyrotechnic fuses, gas detection and fire barriers between battery packs are included within the storage system.
The MEV remains a stationary system in the depot. In contrast, the technically related Max300 is designed for mobility and can be used, for example, as a replacement for diesel generators or to power additional charging points. Pricing for the MEV starts at £70,000. Alternatively, Allye offers the system as “EV Charging as a Service” from £1,900 per month for the MEV200. The first deliveries are planned for the second quarter of 2027.
With its battery storage solution, Alye addresses a well-known challenge in fleet electrification. Often the problem is not a fundamental lack of power at a site, but rather a limitation in the immediately available grid connection capacity. The economic viability of a fast battery charger compared to a grid upgrade depends largely on the location, charging profile, existing connection and costs of a potential grid boost.
allye.com, fleetworld.co.uk, fleetnews.co.uk
