Tektronix: Essential Solutions for High-Power & Battery Testing
The world is rapidly transitioning toward a fully electrified future. This global shift is not just about automobiles. It permeates every sector, from renewable energy grids to consumer electronics. Batteries are the literal power source of this massive transformation. However, they are also complex electrochemical systems. Their safety, longevity, and efficiency depend on rigorous, comprehensive testing.
The Electrification Revolution and its Testing Demands
The demand for reliable energy storage is exponential. For instance, the electric vehicle (EV) market alone is expected to swell dramatically. By 2030, EV sales may constitute over 30% of all new car sales globally. This unprecedented growth drives a critical need for advanced testing equipment. Engineers must confidently verify performance across all stages. This includes cell research, manufacturing, and final system integration.
Tektronix’s Holistic Portfolio for Power Applications
Tektronix, alongside its specialized brands like Keithley and EA Elektro-Automatik, offers a complete testing ecosystem. Their portfolio covers the entire power spectrum. It extends from millivolt-level cell characterization to megawatt-scale battery pack cycling. These tools provide the precision and power required for modern applications. This integrated approach ensures consistent, traceable data. It ultimately accelerates design validation and manufacturing throughput.
The Evolving Landscape of Battery Chemistries
Modern battery technology is not static. Lithium-ion (Li-ion) dominates the current landscape. Yet, new chemistries are constantly emerging. Solid-state, sodium-ion, and advanced lithium-sulfur batteries are on the horizon. Each new chemistry presents unique testing challenges. They require specialized solutions to characterize their capacity and thermal behavior. Tektronix's modular systems, like the EA-BTS series, are designed to adapt. They ensure engineers can remain future-proof as power specifications change.
Foundational Cell-Level and Module Testing: Precision and Throughput
Testing at the cell and small module level is foundational to battery quality. This stage demands the highest degree of measurement precision. Tiny variations in material science or manufacturing quality can drastically affect long-term performance. Tektronix and Keithley provide essential tools here. They ensure that researchers gather actionable, reliable data.
High-Precision Measurements with Digital Multimeters (DMMs) and Source Measure Units (SMUs)
Accurate characterization starts with stable, low-noise measurements. Keithley’s high-resolution Digital Multimeters (DMMs) are critical. They measure voltages and currents with exceptional precision. For example, the DMM7510 can offer -digit resolution. This precision is necessary when assessing minute changes in cell voltage. Such small changes signal crucial internal processes.
The Source Measure Unit (SMU) is perhaps the most indispensable tool. An SMU integrates four instruments into one. It functions as a precision power supply, a current source, a DMM, and an electronic load. This integration eliminates connection errors and synchronization issues. Keithley's 2400 Series SourceMeter SMUs are widely used. They are ideal for battery leakage testing and characterization curves. They can accurately source current while simultaneously measuring voltage (and vice-versa). This capability is fundamental to building an accurate I-V curve for a new cell chemistry.
Open Circuit Voltage (OCV) and Internal Resistance (IR) Testing for Grading
Two key metrics determine a cell's quality and state-of-charge (SOC). These are Open Circuit Voltage (OCV) and Internal Resistance (IR).
- OCV Testing: This test measures the voltage across the cell terminals when no load is applied. Accurate OCV readings, often requiring high-input impedance DMMs, help to precisely grade cells. Cells are sorted into groups based on their OCV. This ensures that only matched cells are assembled into a pack. Mismatched cells drastically reduce the life and performance of the entire battery pack.
- IR Testing: Internal Resistance dictates how much power a battery can deliver or absorb. High IR leads to greater heat generation and lower efficiency. The industry standard often uses the AC Resistance (ACR) method. This method applies a small AC ripple current (e.g., ) to the cell. The resulting AC voltage change is then measured. Specialized Keithley solutions can perform these measurements quickly and reliably. This high-speed testing is crucial for high-volume manufacturing lines.
Cyclic Testing and Characterization for Cell Lifespan
Engineers need to understand how a cell degrades over hundreds or thousands of charge-discharge cycles. This process is called Cyclic Testing. Using precision SMUs or dedicated battery cyclers, current is repeatedly sourced into and loaded from the cell. Critical parameters are tracked over time. These include capacity fade and coulombic efficiency. Coulombic efficiency is the ratio of charge removed from the cell to charge put into the cell. Ideally, this ratio is near . Any deviation reveals internal parasitic reactions. These reactions consume the cell's active material. High-precision measurements ensure that even slight efficiency drops are immediately detected. This provides vital data for validating cell models and predicting lifespan.
High-Power Pack and System-Level Testing: Simulating Reality
Moving beyond individual cells, the challenges of testing full battery packs are significantly different. Packs operate at high voltages (e.g., or ) and high currents. These tests must replicate the extreme, unpredictable conditions of real-world use. This level of testing requires high-power, specialized equipment. It must also feature advanced safety and regenerative capabilities.
Bidirectional DC Power Supplies and Electronic Loads for Battery Cycling
The core of high-power battery pack testing relies on Bidirectional DC Power Supplies. Traditional power supplies simply deliver power. Bidirectional units, however, can both source and sink current efficiently.
- Sourcing (Charging): The unit acts as a precision power source to charge the battery pack.
- Sinking (Discharging/Loading): The unit acts as a high-power electronic load, drawing current from the battery pack.
Solutions from Tektronix's partners, such as the EA Elektro-Automatik or Keithley high-power systems, excel here. These systems provide the necessary power density. They allow for rapid, controlled charging and discharging cycles. This is essential for verifying performance under fast-charging protocols.
Regenerative Technology: Efficiency and Cost Savings in High-Power Testing
Testing large battery packs consumes immense amounts of energy. For example, discharging a pack requires dissipating that energy as heat. This is wasteful and requires large cooling infrastructure. Regenerative technology is the solution to this problem.
High-end bidirectional power supplies feature regenerative capabilities. When the battery pack discharges, the electronic load does not convert the energy to heat. Instead, it converts the DC power back into high-quality AC power. This AC power is then fed back into the facility’s main power grid. The operational benefits are substantial.
- Reduced Energy Costs: Energy consumption can be lowered by up to 90%. This provides massive long-term cost savings.
- Minimized Heat Load: The need for extensive cooling systems is significantly reduced. This simplifies lab infrastructure and lowers maintenance costs.
This technology allows manufacturers to run more tests faster. It is critical for the rigorous, high-volume testing required in modern production.
Drive Cycle Simulation and Battery Management System (BMS) Validation
Testing must move beyond simple constant charge/discharge cycles. Engineers must simulate realistic operating scenarios. Drive Cycle Simulation replicates the dynamic, variable power demands of a vehicle on the road. This involves simulating acceleration, cruising, and regenerative braking events. The test equipment must respond in real-time. It needs to accurately track complex current and voltage profiles.
Crucially, this testing verifies the Battery Management System (BMS). The BMS is the brain of the battery pack. It monitors cell health, controls charging, and ensures safety. High-power test solutions must interface directly with the BMS. They simulate faults and over-current conditions. They confirm that the BMS responds correctly to prevent thermal runaway or damage. Verifying the BMS functionality is arguably the single most important safety step. The dynamic response of the power supply is key to realistic and trustworthy BMS validation.
Beyond Electrical: Thermal and Safety Analysis with Integrated Tools
A battery's performance is not solely an electrical phenomenon. Thermal management and comprehensive safety validation are equally critical. A lithium-ion battery operates within a very narrow temperature window. Exceeding these limits can lead to irreversible damage or, catastrophically, thermal runaway. Tektronix's integrated approach combines high-precision electrical tools with crucial thermal and safety analysis capabilities.
The Importance of Integrated Thermal Monitoring
Temperature directly influences a battery's longevity and power output. Cell degradation accelerates dramatically outside the optimal temperature range (typically to ). High-power testing must incorporate simultaneous, accurate thermal measurements.
Engineers often use thermocouples or Resistance Temperature Detectors (RTDs). These sensors are carefully embedded throughout the pack. Data acquisition systems (DAS) monitor hundreds of temperature points in real time. Tektronix tools often integrate these data streams. This links precise electrical performance to specific thermal conditions. This integrated view is vital for validating the effectiveness of the pack's cooling system (e.g., liquid or air cooling). Any temperature spike needs immediate correlation with the corresponding current load.
Analyzing Switching Losses and Power Quality with Oscilloscopes
The entire power conversion system, or inverter, is intrinsically linked to the battery. The inverter converts the battery's DC power to AC power for the motor. This conversion relies on high-speed switching devices, like Silicon Carbide (SiC) or Gallium Nitride (GaN) power semiconductors.
Oscilloscopes are essential for characterizing these power electronics. Tektronix high-resolution oscilloscopes (e.g., the 5 Series MSO) are used to analyze switching losses. High-frequency switching generates heat. Minimizing these losses maximizes the usable energy from the battery. Probes with high common-mode rejection ratio (CMRR) are needed. These probes ensure accurate measurements of voltages across high-side switches. Accurate analysis leads to optimized gate drive timing. Optimized timing improves efficiency and reduces thermal stress on the components.
Furthermore, these tools measure power quality. They analyze harmonics and ripple effects imposed on the DC link. Poor power quality can stress the battery and other onboard electronics.
Advanced Safety Standards and Compliance Verification
Meeting global safety and regulatory standards is non-negotiable. Testing must verify compliance with standards like UN 38.3 (transportation) and various automotive standards (e.g., ISO 26262 for functional safety).
High-power testing equipment must have built-in safety features. These include emergency stop circuits and over-voltage/over-current protections. The test system itself must be trustworthy. It must reliably execute failure modes without causing physical damage to the expensive battery pack or the facility.
