Thermal monitoring for battery storage systems.

Battery Energy Storage Systems (BESS) are essential for storing renewable energy and ensuring grid stability. However, their implementation comes with inherent risks, particularly related to lithium-ion battery fires.

ESS fires can start from thermal runaway, where one cell failure can trigger a cascade of overheating, leading to fires that are difficult to extinguish and can last for hours or even days. Should a fire breakout, hazardous gases would release from the batteries, posing health risks to nearby communities and causing environmental damage through soil and water contamination. In severe cases, BESS fires have the potential for huge disruptions to locals through property damage and even evacuations.

Traditional detection methods such as flame detectors often fail in the early stages of a BESS fire due to their reliance on visible flames or smoke, which might not be immediately present. Where flame detectors fall short, thermal imaging cameras can significantly improve protection and prevent fires before they ever reach combustion.

FLIR A700F Advance Smart Sensor

Advantages of Thermal Cameras for BESS.
Thermal cameras detect the heat signature from the onset of thermal runaway long before visible flames or smoke appear, allowing for preemptive action to mitigate risks. While flame detectors react to events that have already happened, a fixed thermal camera such as the FLIR A700F Advance Smart Sensor provides 24/7 surveillance by continuously monitoring for temperature anomalies that could indicate an impending fire, thus enabling early intervention. FLIR cameras are designed for easy integration into broader safety and control systems, allowing for automated responses such as activating suppression systems that enhance response times and efficiency.

Comparison with Other Detection Methods.
While flame detectors are designed to detect visible fire, they may miss smoldering or hidden fires—meaning an alert may not be tripped until the fire has escalated to a dangerous level. FLIR thermal imaging cameras can detect heat in low light and see the beginnings of embers as they heat up surrounding materials, even when there's no visible sign of fire. This early detection can prevent escalation or at least minimize damage by providing critical time for action before fires get out of control. Another advantage of thermal cameras is their ability to monitor large areas or multiple battery racks simultaneously, providing comprehensive coverage which is often challenging for point-specific flame detectors.

Conclusion. Incorporating FLIR thermal monitoring into BESS installations not only addresses the critical safety concerns associated with battery fires but also offers a proactive, reliable, and technologically advanced solution. By choosing a FLIR fixed thermal solution, you ensure that your energy storage systems are safeguarded with the industry's leading thermal imaging technology, protecting both your investment and the community from the devastating effects of BESS fires.

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@flir @mepaxIntPR #PAuto #Battery

Battery analysers simplify maintenance and performance testing of stationary batteries and battery banks!

Fluke has introduced a range of battery analysers for simplified maintenance, troubleshooting and performance testing of individual storage batteries and battery banks used in critical battery back-up applications. The compact and rugged Fluke 500 Series Battery Analysers cover a broad range of battery test functions, ranging from manual DC voltage and resistance tests, to full condition testing using an automated string function testing, and a test probe integrated infra-red temperature measurement system. They have been specifically designed for measurements on stationary batteries including GEL, AGM (Absorbed Glass MAT) and float open cells.

The entry-level Fluke BT510 Basic Battery Analyser features an intuitive user interface for manual and automated sequence testing of battery strings with automatic storage of readings including voltage and resistance. The Fluke BT520 Battery Analyser and Fluke BT521 Advanced Battery Analyser come with an enhanced interactive test probe set, featuring an LCD display and verbal audio feedback, which increases throughput by allowing the user to perform all necessary test functions from the test probe itself. The BT520 and BT521 also come with an attachable LED flashlight.

The Fluke BT521 test probe features an additional sensor for temperature measurement of the negative battery post, and the BT521 comes with a current clamp and measurement capability for DC and AC currents and frequencies. The BT521 also features Bluetooth wireless communication to provide data to an iPhone app.
FlukeView® Battery Management software included with each model provides enhanced data analysis, with fast data download from the battery analyser via a USB port. The software enables quick trend comparisons, results analysis and creation of graphics and tabular reports. The rugged mainframe construction and rugged probes with replaceable probe tips have been designed to meet the demands of repeated testing; decreasing failure rates and reducing cost of ownership

Battery testing made simple!

The new EL97xx series of electronic loads available now from Interpro offers users a simple means to test or characterise individual battery cells or multi-cell stacks.

Models are available with power ratings from 150 to 6,000W for use as simple front panel controlled bench test or repair instruments to components in complex, automated test and burn-in systems. Applications include repair of power supplies and equipment through to testing batteries used for high reliability UPS and data-protection systems. Comprehensive battery testing can identify individual faulty cells allowing battery stacks to be rebuilt, reducing waste and recycling while improving reliability. Battery manufacturers can use the Intepro EL97xx series of electronic loads to characterise the performance of new designs, establish life expectancy and for production test. Automated testing provides repeatability and offers storage of test data for quality control, analysis and traceability. Test results may be fully interrogated and exported as spreadsheets or word documents into a SQL database.

All Intepro EL97xx electronic loads are supplied with comprehensive free software to simplify set-up and testing of batteries. Dynamic burn-in and discharge tests with user control of waveform may be simply performed with all test parameters available for user setting, live data is shown on a virtual control panel and a clear “capacity plot” is displayed. The user can add additional markers by using the icons on the tool bar to set a visual indicator to show the expected performance range. As well as being a standalone instrument the EL97xx electronic load is also designed for easy integration into larger automated test systems and may be controlled bytheir open-source PowerStar software suite.

Simon Tanner, European Sales manager comments, “Battery testing can be difficult and time consuming. Our new EL97 range of flexible competitively priced electronic loads provide built-in battery test functions with easy to use computer control which go together to make the process of testing batteries simple, repeatable and low cost. The inbuilt test reporting also provides data for traceability and quality assurance which add up to providing confidence in your product for your end customers.”

Intepro EL97xx electronic loads are very competitively priced and ideal for research and development, inspection, service and test requirements in industry, research laboratories, training centres and education. The loads have an input rating of 0-500V, may be combined to provide greater than 6,000W of load, a 2 year warranty and are available on a 4 week lead-time.

EL97xx electronic loads enable testing of any current carrying component (e.g. connectors and terminals) and a wide range of dynamic load conditions may be simulated including solar cell and fuel cell loading, LED testing and battery discharge profiles. 6 modes of operation (CC, CR, CV, CC+CV, CR+CV) are available with fast rise-times and dual range 16-bit resolution measurements are performed with the accuracy of a digital multi-meter and the convenience of a single connection. The loads are fully protected against OP, OC, OV, OT and reverse polarity ensuring operational reliability and protection for the device under test. Special features include 999 measurements/hour, constant current mode soft-start, dynamic pulsing and programmable duty cycles.

Hybrid/Electric battery monitor

The LTC 6804 high voltage battery monitor from Linear Technologies, is for hybrid electric and electric vehicles, and other high voltage, stacked-battery systems. An LTC6804 can measure up to 12 series connected battery cells at voltages up to 4.2V with 16 bit resolution and better than 0.04% accuracy. This high precision is maintained over time, temperature and operating conditions by a sub-surface Zener voltage reference similar to references used in precision instrumentation. When stacked in series, the LTC6804 enables the measurement of every battery cell voltage in large high voltage systems. Six operating modes are available to optimize update rate, resolution and the low pass response of the built-in 3rd order noise filter. In the fastest mode, all cells can be measured within 290µsec.

Multiple LTC6804s can be interconnected over long distances and operated simultaneously, using Linear Technology’s proprietary 2-wire isoSPI™ interface. Integrated into every LTC6804, the isoSPI interface provides high RF noise immunity up to 1Mbps and up to 100 meters of cable, using only twisted pair. Two communication options are available: with the LTC6804-1, multiple devices are connected in a daisy chain with one host processor connection for all devices; with the LTC6804-2, multiple devices are connected in parallel to the host processor with each device individually addressed.

The LTC6804 was designed to minimize power consumption, especially during long-term storage where battery drain is unacceptable. In sleep mode, the LTC6804 draws less than 4µA from the batteries. General purpose I/O pins are available to monitor analog signals, such as current and temperature, and can be captured simultaneously with the cell voltage measurements. Additional features include passive balancing for each cell with a programmable balancing timer for up to 2 hours, even when the LTC6804 is in sleep mode. The LTC6804 interfaces with external I2C devices such as temperature sensors, ADCs, DACs and EEPROM. Local EEPROM can be used to store serialization and calibration data, enabling modular systems.

The LTC6804 was designed to surpass the environmental, reliability and safety demands of automotive and industrial applications. The LTC6804 is fully specified for operation from -40°C to 125°C. It has been engineered for ISO 26262 (ASIL) compliant systems and a full set of self-tests ensure that there are no latent fault conditions. To accomplish this, the LTC6804 includes a redundant voltage reference, extensive logic test circuitry, open wire detection capability, a watchdog timer and packet error checking on the serial interface.

“The LTC6804 combines 30 years of analog experience with hard-earned lessons in automotive battery management,” says Mike Kultgen, design manager for Linear Technology. “On the bench, or on the road, this part delivers outstanding performance.”

Along with the LTC6804, Linear Technology is introducing the LTC6820 isoSPI transceiver. The LTC6820 enables bidirectional transmission of the Serial Peripheral Interface bus (SPI) across an isolated barrier up to 100 meters. With the LTC6820, the SPI data is encoded into a differential signal, which is then transmitted via twisted pair and a simple, inexpensive Ethernet transformer. The LTC6820 supports SPI data rates up to 1MHz, using matched source and sink currents to eliminate the need for a transformer center tap and to reduce EMI. The drive currents and the comparator thresholds are set with two resistors, allowing the system to be optimized for cable length and signal-to-noise performance. The LTC6820 is a companion to the LTC6804 high voltage battery monitor with its built-in isoSPI interface.  Battery management systems using the LTC6804 can interface to external components, such as microcontrollers, via the LTC6820.

Battery monitor

LEM has announced the introduction of Sentinel 3+, the latest generation of the proven Sentinel product that continuously monitors the state of health of batteries in uninterruptible power supply (UPS) systems. The enhancements incorporated in Sentinel 3+ enable it to be fully integrated into the newest architectures of UPS, accommodating UPS design evolutions such as transformerless circuit topologies.

• Advanced battery monitoring components track latest changes in UPS design practice
• Uprated robustness, improved EMC performance and enhanced noise shielding maintain measurement performance
• Offered as a portfolio of measurement components, or complete monitoring platform for incorporation in to battery systems
• Dedicated and hardened bus communicates comprehensive data to supervisory systems

Sentinel 3+ is a battery-monitoring transducer that makes measurements of voltage, temperature and impedance, of cells and complete batteries, in UPS installations of all sizes up to mega-watt back-up power supplies for data centres and hospitals. Sentinel 3+ reports its measurements – on VRLA (valve-regulated lead-acid), gel or flooded stationary batteries – to supervisory systems over a dedicated communications bus, and offers a unique capability to assess the true state-of-health of UPS batteries while they are in service. Sentinel 3+ gives complete confidence that battery arrays will deliver their rated power when called on to do so, and identifies weak and failing cells without the need to remove them from service for cycling tests.

Designers of the latest UPS systems have exploited technology developments such as the availability of fast IGBTs (insulated-gate bipolar transistors) to reduce costs by eliminating bulky and expensive transformers from their circuit configurations. The battery packs that the Sentinel product monitors are, in consequence, operated in a floating voltage mode: the battery is subjected to higher ripple currents, and the monitoring circuitry must handle high common-mode voltages, with superimposed high-amplitude, fast transients.

LEM's Sentinel 3+ features upgraded algorithms to take account of this more challenging measurement environment, maintaining the well-proven accuracy of the Sentinel product family, as well as improved EMC immunity and enhanced overall robustness. Sentinel 3+ delivers voltage measurements over a range of 0.9 to 16V with an accuracy of +/-0.5%; impedance measurement from 0.05 to 250 mΩ with repeatability of +/-2%. Sentinel 3+ features Common Mode Transient Immunity up to 20 kV/µsec with a common-mode voltage level of +/-600V, and a transient repetition rate of 20 kHz.

2nd generation high voltage battery stack monitor

Linear Technology has announced the LTC6803, a second generation high voltage battery monitor for hybrid/electric vehicle (HEVs), electric vehicles (EVs) and other high voltage, high performance battery systems. The LTC6803 is a complete battery measuring IC that includes a 12-bit ADC, a precision voltage reference, a high voltage input multiplexer and a serial interface. Each LTC6803 can measure up to 12 individual battery cells in series. The device’s proprietary design enables multiple LTC6803s to be stacked in series without optocouplers or isolators, permitting precision voltage monitoring of every cell in long strings of series-connected batteries. The LTC6803 follows the road-proven LTC6802, introduced in September 2008 with the same functionality and pinout, plus a number of significant performance enhancements.

The maximum total measurement error of the LTC6803 is guaranteed to be less than 0.25% from -40°C to 125°C. The LTC6803 offers an extended cell measurement range from -300mV to 5V, enabling the LTC6803 to monitor a wide range of battery chemistries, as well as supercapacitors. Each cell is monitored for undervoltage and overvoltage conditions, and an associated MOSFET is available to discharge overcharged cells. Added functionality is provided by an onboard 5V regulator, temperature sensor, GPIO lines and thermistor inputs.

Erik Soule, Vice President, Signal Conditioning Products, stated, “Now over two years in the field with our proven battery stack monitor family, we are pleased to offer our customers this enhanced product, the LTC6803. Automakers and other customers worldwide have embraced Linear’s robust battery stack monitors, and we are confident that this new addition to the family will provide excellent performance for the next generation of HEVs and EVs.

“The LTC6803 addresses the latest demands of precision high performance battery stacks,” says Mike Kultgen, design manager for Linear Technology. “It ensures accurate, safe, reliable and error-free operation in harsh automotive environments.”

For long-term battery pack storage, the current consumed by the integrated BMS can potentially unbalance the cells. The LTC6803 addresses this concern with a standby mode that draws less than 12uA. Furthermore, the power input of the LTC6803 is isolated from the stack, allowing the LTC6803 to draw current from an independent source. When powering from this input, the current draw on the pack is reduced to less than 1µA.

The LTC6803 is designed to surpass the environmental, reliability and safety demands of automotive and industrial applications. The device is fully specified for operation from -40°C to 125°C. It has been engineered for ISO 26262 (ASIL) compliant systems and a full set of self-tests ensure that there are no latent fault conditions. To meet this standard, the LTC6803 includes a redundant voltage reference, extensive logic test circuitry, open wire detection capability and a watchdog timer for fail-safe designs. The LTC6803 is designed to withstand up to 75V, providing more than 20% of overvoltage margin for a full string of 12 cells. The 1MHz serial interface includes packet error checking and is designed to operate in the presence of large amounts of noise and transients.

The LTC6803 is offered in a small 8mm x 12mm surface mount device.