What type of maintenance does a Corvus Energy System require?
Corvus Energy Storage Systems (ESS) are designed as a solid state unit that is resistant to water, vibration, impact and electromagnetic interference (EMI). They require no maintenance after commissioning and are designed to provide years of reliable service. The system performance may be monitored from any location in the world using the Corvus Gateway monitoring system. Not only may the state of health, state of charge and many other parameters may be monitored remotely, the Corvus Gateway also allows for remote software upgrades as required.
What is the chemistry used in the batteries?
The Corvus Energy lithium ion batteries are based on a patented Nickel Manganese Cobalt (NMC) Polymer chemistry. NMC Polymer provides approximately 25% more energy and power density compared to Lithium Iron Phosphate (LiFePO) formulas. When combined with the ultra low internal resistance of the cell, the batteries provide a much higher usable power source that may be used to replace diesel scale power in many industrial applications.
How safe is the NMC Polymer battery from Corvus Energy?
As a marine focused company, Corvus Energy is committed to providing the safest products without compromise. NMC Polymer is one of the safest lithium chemistries available and when combined with software and mechanical fail safes, provides an unparalleled level of safety. Additionally, Corvus Energy has integrated a unique Battery Management System (BMS) that manages voltage, current and temperature in order to keep the battery in a safe working mode at all times. External communications with vessel system components create an inherently safe overall system. In the event of a failure beyond the scope of the Corvus ESS, the system will enter a controlled shut down mode. If further mitigation is required, the Corvus ESS communicates with fire suppression systems. Further, the mechanical design of the components inherently resists thermal runaway and in independent testing laboratories has proven to contain it to one module, with no external fire.
Do the batteries need cell balancing?
Unlike others in the industry, Corvus Energy has integrated passive cell balancing in the battery as a standard. Cell balancing provides peak performance of the battery system and maximizes system lifespan. Passive balancing eliminates complex and potentially unsafe active balancing systems as a potential risk of fire or failure.
How does the cell balancing from Corvus Energy work?
The Battery Management System (BMS) of Corvus Energy is a proprietary system that works automatically to equalize all cells in a pack. With this system not only is the battery kept safe but also more usable capacity is provided.
Does the Corvus Energy lithium ion battery require any special handling?
All lithium batteries are considered dangerous goods for transportation purposes. However the battery itself does not require any special handling beyond normal precautions of any battery. With each system installed, Corvus Energy will approve external user connections and provide commissioning services.
What is the voltage and capacity?
The Corvus Energy Storage System is based upon a 50V standard module (50V at 150Ah). This module may be connected in series up to 1050V as required by the customer. Standard capacity is rated at 6.5 kW-hr nominal. 96V 75Ah modules are available in limited quantity runs.
Can the lithium ion be paralleled to create bigger battery banks?
Yes, due to the integrated BMS system, there are no restrictions in paralleling the batteries.We are currently engineering packs to 100MWh, but there are no technical limits to capacity.
Can the lithium ion be connected in series to create a high voltage pack?
Yes, due to the integrated BMS system it is possible to connect multiple battery modules in series, to create a high voltage pack our standard system may be configured in increments of 50V up to 1050V with unlimited capacity.
What is meant by a 1C discharge or charge rate?
The C rate for charge or discharge is simply the amp-hour rating of the battery normalized to a value quoted at 1C. For example, a 200 amp-hour rated 12V battery, being charge at a 1C rate, would require a charger capable of delivering 200 amps at 12 volts and would charge the battery in one hour. A 2C charge rate would be 400 amps and would charge the battery in 0.5 hour. One of the significant advantages of the lithium batteries over lead acid is their inherently high C rate for charging.
Will the batteries support high discharge rates?
Yes for very short bursts up to 10C. This would be beyond the scope of normal operation.
Will the batteries accept high charge rates?
Yes the recommended maximum charge rate is 2C (1/2 hour) for long battery life, but 3C (20 minutes) may be allowed depending on the available charging system. All charge functions will be controlled and supervised by the BMS.