Fire Suppression Lithium Batteries is critical for Large Commercial Micro-grids:
Let's look at large commercial 100kWh up to 1MWh from Safiery first:
Two minutes over-charging a lithium battery at 100% State of Charge results in thermal runaway.
If not properly managed, thermal runaway can lead to intense fires. This becomes even more critical if the thermal runaway propagates through the battery array. Common causes of thermal runaway include over-charging, over-discharging, high or low temperatures, or latent manufacturing defects.
Fire Protection drives the Design of Lithium Batteries in large Commercial Off grid Systems.
Lithium batteries dominate the short term energy storage market because of their high efficiency and energy density. Energy transfer rates are often pushed to the limit. With that comes the increased risk of fire. Two Tesla’s megapacks caught fire in 2021 and a similar incident at a Sinexcel BESS container.
Insurer’s will factor into premiums a certain level of risk but there comes a point where they will back away from the business. This article is about technology changes that significantly reduce risk for an acceptable insurance premium.
Insurers want to see state-of-the-art compliant fire protection that's made up of multiple layers right down to the cell level. It's no longer a matter of placing rack mounted lithium batteries in a cabinet with an overall cabinet fire suppression system. Those days are over for 100kWh plus Micro-grids.
Time and Temperature Monitoring
Although in the example above, it took 15 minutes for the problem to develop to a critical stage, action is needed well before that. In order to detect stage II quickly, each battery module needs individual cooling to maintain a sub 50C temperature band. This keeps the module at a relatively low temperature to start with. The battery module is also separated with insulating walls. Temperature is measured at the cell level with Cell Min and Max values across the array displayed.
Double Level Fire Suppression
The battery array is designed with multiple layers of independent thermal detection and fire suppression: at each individual battery module and then the entire cabinet containing all the battery modules. This is done with active venting, aerosol suppression and pressurised water flooding of the battery array in the cabinet. We bring a smile to your insurer!
Power Control System (PCS) and Battery Management System (BMS)
Although the BMS will always protect the battery, the power control system, which charges and discharges the batteries, is integrated with the BMS to reduce power before the safety systems engages. Together, these pair optimize the charging and usage of batteries, significantly extending the batteries lifespan and reliability. They also monitor and avert potential thermal events.
However, the insurer may not accept a software only solution from the Battery Management System to mitigate the risk in large commercial grade off-grid systems. Multiple Independent Sensors and Protection is required.
Regulatory Compliance
Compliance with standards to Class 3 Fire Protection is essential for the safe design and operation of Mirco-grids with lithium batteries. These standards provide guidelines for fire protection, including design density, separation distances, and fire resistance ratings.
Class 3 fire protection for lithium battery systems involves a combination of early detection, effective suppression, proper compartmentation, ventilation, and adherence to regulatory standards to mitigate the risks associated with lithium battery fires.
Megaflex uses Novec 1230 used for Fire Suppression
Novec 1230 is a versatile, environmentally friendly fire suppression agent that offers effective protection for sensitive environments without the drawbacks of traditional agents.
It works by rapidly absorbing heat, thereby extinguishing the fire before it can spread. Novec 1230 is stored as a liquid and discharged as a gas, leaving no residue and causing no damage to sensitive equipment.
Non-conductive: Safe for use around electronic equipment.
Low Toxicity: Safe for human exposure at typical concentrations.
Eco-friendly: It is considered environmentally benign compared to traditional halon and HFC agents.
SIZE MATTERS
Footprint
1055mm x 1645mm x 2398mm (fixed base included)
Energy Density
147kWh/m2
Expansion Off grid
Up to 5 units can be joined off grid:
Up to 5kVA
Around 1.2 MWh of safe energy storage.
400kw @ 415v 3Phase power provided for almost 3 hours.
100kW @ 415v 3Phase power provided for around 10.0 hours.
Our Off-Grid Micro Grid Solutions are growing !
The fully engineered latest addition to our Micro Grid family, the Megaflex range is now available for order.
This intelligent energy dense solution is perfectly suited for large applications where critical power is required be it EV, emergency back up or complete energy autonomy from the grid like an off shore island !
Certified for the Australian and New Zealand markets, the enclosure is extremely safe with thermal run away protection, fire suppression and prepared for water flooding.
It includes premium battery technology , highly efficient power conversion and managed by our own Australian designed and built Micro Grid management system which includes solar, grid, wind and a generator if desired.
Small Lithium Installations still have safety requirements:
Safiery insist on the highest quality cells at 3mV max differential compared to most in industry at 10mV.
The greatest risk to thermal runaway in RV/Marine lithium battery installations is when charging:
For Australian/NZ Marine Compliance:
- The Battery must have IEC 62619 Certification.
- The Lithium battery MUST give a "Stop Charge" signal.
- The Cell voltage min and max must be visible on a display
- The Cell Temperature Min and Max must be visible on a display
Safiery's Meteor Batteries comply with this standard when used in conjunction with a Victron Energy GX system.
Safiery Meteor Battery Cell Selection during manufacture:
- Has a 0.003V maximum band when rested.
- The picture on right shows 0.002V. That is 2 thousandths of a volt difference between the maximum cell voltage and minimum cell voltage in the battery train.
What this high quality means for the user :
- There is a lower probability of thermal runaway when charging because of cell voltage differences.
- There is less energy wasted during active cell balancing.
- The battery will have a higher retained energy when agred.
- Tests show 82% retained energy after 4,700 cysles. (max on test bed so far).
