Archimede Energia lithium accumulators approved according to the requirements of the CEI 0-21 standard

The bi-directional storage system, consisting of Archimede Energia batteries, has obtained CEI-021 certification following passing the tests required by the standard.

The bi-directional storage system is composed of two fundamental elements:

  • Archimede Energia accumulators: LiNMC 48.1 Vnom, 150 Ah for an available energy of 7.21 kWh and a continuous discharge power of 9.76 kW.
  • Inverter: Leonardo Pro 5000/48 Li. Nominal power 4 kW, 230 Vac-50 Hz. Communication with Archimede Energia accumulators via CAN Bus.

The ARCHIMEDE ENERGIA accumulator proposal for domestic on-grid systems provides for an available energy range from 2.8kWh to 50.4kWh.

The hardware and software technical skills, entirely available in ARCHIMEDE, were used in an optimal manner in order to make our systems compliant with Italian legislation and thus provide current and future customers with a system ready for integration into the network.


  • The legislation is mandatory by law to obtain and maintain the connection of the electrical system to the national distribution network. These standards, in fact, establish how to physically connect the storage system according to different possible schemes, which include the various devices involved (battery, inverter, meters).
  • The adaptation to the CEI 0-21 connection standards for low voltage serves to demonstrate that the modification of the new system or that the existing one is expanded are respected.
  • CEI-021 is a MANDATORY document BY LAW which certifies the compliance of the storage system to be connected to the public network. This reference is essential for the connection of active and passive users to low voltage (LV) networks.


The system is ideal for both new photovoltaic systems and for adding a storage system to photovoltaic systems already equipped with AC on-grid string inverters. Compatible with the installation schemes envisaged by CEI-021 without altering the quantity of energy produced and encouraged.

the system, in the event of a blackout of the electricity network, powers the connected users with a recovery time of less than 10 ms.

In the context of storage inverters, bi-directional inverters are also able to draw energy from the grid to recharge the batteries. This function, which may not seem economically advantageous, may instead prove necessary to ensure a long life of the battery avoiding deep discharges (for example in the case of photovoltaic failure).

It can also be used to ensure a certain stored energy and then make it available at times of greatest demand (peak shaving) or when it is economically more convenient.