Lithium Batteries: Advances in Intelligent Communications
Off Grid Power Storage Systems charged by Solar PV and Generators provide a critical Independent power supply for Residential and Commercial applications. With recent advances in technology, the quality, capacity and communications of battery technology have created a new landscape of opportunity.
OUT WITH THE OLD
Up until 2 years ago traditionally 2V and 12V AGM Lead-Acid cells have been the bedrock of energy storage. This has all changed as rack-mounted Lithium batteries have come onto the market, creating compact and modular capacity.
The pictures below show comparative sized systems with the same capacity from 5 years ago against projects from this year. What once required an entire floor is now achieved with only a few lithium batteries using a fraction of the space.
My how far we have come along!
NEW STANDARDS IN BATTERY TECHNOLOGY
Installers have soon learnt how not all batteries are alike however. Many entry-level Lithium batteries do not have the capacity for high current power draws, fast charging and daily cycling (all necessary for commercial use in an unstable Eskom power grid), nor do they have the required inverter CAN Bus communication.
At the heart of Lithium Power Storage is the Battery Management System or BMS. This key online monitoring component that supports the batteries, and manages communications between the inverter and the batteries is controlled through CAN Bus. This is where the revolution starts
Without CANBUS the SOC is based on the average voltage of the battery system. So even though the online BMS says the batteries SOC is full there may be cells in the bank that are not at the same levels of charge. With CAN Bus, we can measure the start of charge at an individual cell level.
This has major consequences when we are faced with driving the energy efficiency through night time Battery Discharging and Load shedding
backup capacity – it is essential to accurately know what your batteries’ State of Charge is. Especially when there are cloudy days, or when the full the system is not able to equalize.
In close consultation with our manufacturers and with the experience of dozens of installations, we have ensured the compatibility of our Sunsynk Inverters and Revov Lithium Batteries, which operate via CAN Bus.
LOOKING TO THE FUTURE
Blue Sun is now launching Hybrid 3Phase Sunsynk 10KW and 12KW Hybrid inverters. In addition to having larger Solar MPPT capacity PV Input (1000VOC), they also provide even greater Battery charging and discharging current (240A).
As our systems have developed with greater 3-phase capacity, a range of off-grid systems possibilities have arisen for commercial applications. From EV charging in City buildings to power shortfall for manufacturing.
Our power systems will provide compact and intelligent capacity, where it was not previously possible.