The main principle of the Amvolt battery storage concept is technical openness, i.e. no vendor lock-in for our customers. This of course also applies to our high-voltage battery storages. Unlike smaller Amvolt low-voltage Energy Boxes and Modules for indoor use, Amvolt high-voltage storage systems come with their own specially developed inverters. They are connected to a mains voltage of 3 x 400 V AC and inside the prismatic LFP cells are connected to a voltage of approximately 700 V. Our BESS containers are made of 71,7 kWh standardized, modular battery boxes and there can be up to 14 of them in a 40-foot container, so 1000 kWh in total. All completely assembled in the Czech Republic.
In contrast to closed "shelf" storage solutions, Amvolt storage systems use prismatic LFP battery cells (easy to replaceable individually), to which we have a good strategic approach, and the electrical components (BMS, protection, etc.) are handled in the form of industry-standard modular devices from western suppliers.
Customers of Amvolt Battery Containers are owners/operators of LDS, large PV plants, MVE, industrial sites, etc.
Amvolt container storage systems are sold in consortium with carefully selected regional suppliers, including control system and monitoring (optional), installation and commissioning, usually as a complete PV plant service. Thanks to large-capacity storage, customers also get the possibility to participate in trading (VDT, DT) and SVR in the future (now also, but more difficult, depending on the region). We can also facilitate and help set up such services.
Amvolt battery storage systems, whether Battery Containers or Battery Packs for indoor usage, are assembled in a modular and tailor-made manner. We use industrial LFP (LiFePO4) prismatic cells of world-renowned brands Winston and Elerix, which are supplied by our parent company GWL a.s.
The cells are characterized by high safety and long service life, they are non-flammable and non-explosive. The usual lifetime of a cell is up to 8 thousand cycles, but even after that, the cells can be used for many more years without any problems. In the event of damage to some of the cells in the storage unit, the other cells can be reassembled and used again or the individual cells can be replaced – so the entire storage unit is not damaged, as is the case with closed battery packs and containers.
That's why for each Amvolt storage unit, we always recommend purchasing spare cells with a capacity of 1–5 % of the total capacity. You can learn more about LFP battery cells in the Technology section.
The Amvolt HV 750/200 inverters (AC mains – DC battery) manufactured in the Czech Republic are one of the main advantages of Amvolt high-voltage container solutions. Thanks to the inverter custom developed for Amvolt, our Battery Containers do not need a transformer or DC/DC converter, which increases reliability and reduces losses.
The control processor electronics of the inverter ensure the quality of the required parameters for connection to the distribution network. The inverter is phase symmetrical and fully reversible, i.e. it can charge and discharge the battery at full power and the transition from charging to discharging mode is a matter of tens to hundreds of milliseconds. It is suitable for almost unlimited parallel wiring and thus unlimited power scaling.
The inverters are hydraulically cooled, reducing the thermal management requirements of the BESS internal environment. Waste heat is immediately removed from the battery compartment and radiated to the surrounding environment. With a low-temperature gradient of only 2 °C, the inverter can be easily cooled passively even in the summer months. The inverter is controlled by an internal PLC unit based on standardized WAGO modules.
Amvolt Battery Containers are composed of a selected number of the basic Amvolt high-voltage (650–800 V) module 71.7 kWh battery boxes. Each of these battery boxes consists of two parts:
a) The individual battery cells with the BMS system are located on the right side of the box.
b) The master module of the BMS system and all of the battery cabinet's circuit breaker power elements are located in the left part of the battery box. The cable exit from the box is routed upwards.
Each Amvolt 71.7 kWh battery box contains 224 pieces of Elerix EX-L100K cells with a total nominal voltage of 720 V and a capacity of 100 Ah. These battery boxes are connected in parallel on a DC bus with the same nominal voltage.