Grid-scale and stationary energy storage systems are a critical part of our future.
Arbin provides battery test equipment for cells, strings/modules, and packs of all sizes to meet demands of stationary storage applications ranging up to 1MW in power!
Read more below about how our equipment is optimized to test grid storage batteries.
The power grids that supply electricity to homes and businesses around the world are growing every year. There is also a global trend to transition energy generation from fossil fuel-based generation to renewable sources such as wind, solar, hydro, and others.
Energy storage plays a role to assist both requirements by allowing the power gird to store energy locally and operate more efficiently. Similar to electric vehicles (EV’s), the massive energy storage systems required for grid-scale applications need to operate for an extended 10+ years of life and withstand many thousands of cycles.
How Energy Storage Systems Help the Power Grid
Key reasons how the power grid benefits from energy storage are by supplementing peak capacity requirements and the use of micro-grids or distributed energy storage.
Peak Shaving – peaking capacity can be a concern for grid storage system operators. The operators must ensure that during peak demand times, the grid has enough energy to avoid being overrun with demand. This is where the battery energy storage system (BESS) that collects energy and releases it when needed comes in as a backup. Grid-scale battery systems are able to supplement the growing peak capacity requirements, so the energy generation does not need to increase overall capacity to accommodate these extreme conditions.
Distributed energy storage allows smaller, more efficient power distribution networks at a local scale, and contributing to microgrids. Microgrids can function autonomously or as part of a larger power gird system. They require sources of energy generation, typically involving renewables such as solar, wind, and large battery packs to store the energy.
The distributed energy storage systems:
- Provide support for renewable energy generation
- Allow frequency regulation and improve power quality
- Load shifting so power can be stored when costs are low and discharged when costs are higher
- Provide backup power during outages
Battery Testing for Grid Storage Applications
Arbin’s battery test equipment is divided into Cell, Module, and Pack level as defined by voltage of the device(s) being tested.
Choose the appropriate section below to navigate directly to the test equipment pages, or read below for more information.
Batteries are the critical component in energy storage systems that determine performance under specific operating conditions. It is important for batteries to provide enough energy for the load, temperature conditions, and duration they will experience during its useful life. Battery manufacturers provide general specifications for their cell or module performance, but these need to be evaluated in combination with application-specific parameters.
Typical performance indicators will include discharge performance under various conditions, peak discharge current, internal resistance, endurance cycling, energy efficiency metrics, and more. These metrics will serve as a baseline performance comparison for different types of batteries being evaluated for a grid storage system.
Why Using The Right Test Equipment Matters
One of the biggest challenges for utility providers is the uncertainty over how batteries will perform and last over time. High quality test equipment can facilitate more accurate projection of the lifetime performance of a battery.
High resolution and high precision equipment like Arbin’s ensure that any slight change or differentiation between cells or battery packs is observed and analyzed by engineers. All Arbin cell testers have industry-leading 24-bit resolution, 256x higher than the industry standard of 16-bit. This allows for high clarity in testing data when combined with Arbin’s high precision circuitry developed during a joint project between Ford Motors, Sandia National Lab, Montana Tech, and funded by US DOE ARPA-E.
Dynamic test profiles are crucial for testing grid energy storage. Traditional battery testing may cycle with constant current charge/discharge cycles (CC-CV). However, grid storage applications, especially when connected to a renewable energy source, do not have constant charge/discharge activity. Instead, the batteries have very dynamic charge and discharge profiles that need to be replicated to compare the performance between battery systems or when predicting the long-term life.
Arbin’s software makes dynamic testing easy by allowing users to simply upload time-based [current, power, or load] data without additional programming. The system can safely handle millions of data points with intervals as fast as 10ms.
All Arbin testing systems also utilize an advanced true bipolar circuitry, so there is also no switching between charge and discharge when simulating these very dynamic charge/discharge profiles. Older style test equipment without this feature will experience undesired pulses and drops in current output during the relay switching. This skews results data over time. Thus, true bipolar circuitry is critical to perform accurate simulations that replicate how a battery will charge or discharge in real life.
Regenerative (Back-to-Grid) Testing
Arbin uses state-of-the-art regenerative circuitry for all high-voltage/high-power applications. Energy storage systems for grid-scale applications commonly need to be tested at 100’s of kW. Arbin’s regenerative “RBT” test equipment is provided ranging from 2.5kW up to 1MW in power!
High efficiency circuitry and power density minimize the cost of operation compared to similar equipment.
- Power Factor > 0.99
- Regenerative Efficiency > 92%
The fully integrated, turn-key system from Arbin provides better performance and safer operation compared to rack-mounted e-load + power supply solutions.
- Control Accuracy < 0.05% [Industry leading]
- Multiple Current Ranges per channel
- Current Rise Time < 10ms
- Synchronized data logging at 10ms
- Optional auxiliary inputs are fully customizable by the user and can be flexibly mapped with main I/V channels in any configuration. All data is integrated into a single Arbin database.
Thermal safety is a key factor that can affect battery stability and safety. Grid storage systems are often located outdoors and are thus exposed to the elements and changes in weather and ambient temperature. Arbin has created an innovative new temperature chamber for testing individual cells known as the “MZTC” Multi-Chamber. This cell-isolating battery test chamber isolates each cell or pair of cells (depending on cell size and amperage) to create a safer test environment and maintain greater temperature stability. Each of the 8 mini-chambers offers a unique temperature setpoint and is thermally isolated from the others to prevent thermal run-away or cascading failure events. Arbin’s MZTC battery test chamber also makes connections and interfacing with cells easy.
Arbin also has the option to interface with a variety of third-party temperature chambers from other manufacturers. The software is compatible with most major chamber controller models around the world, so the Arbin tester can automatically turn the chamber on and off, and adjust temperature during the test. Check with your local Arbin sales rep to learn more. [Arbin Contacts]
Grid energy storage systems will become more and more widely adopted when the safety of the system can be assured. Battery test equipment must help determine the parameters within which batteries can operate safely while also maintaining a safe test environment.
Arbin’s MZTC Multi-Chamber allows cells or pairs of cells to be isolated into individual chambers. Each of the chambers can be set to unique temperatures and is thermally isolated from other cells in order to prevent thermal runaway or cascading failure events. This makes testing batteries at different temperatures much more efficient.