Stage Lighting Battery Pack: Fix Voltage Sag and LED Flicker

Stage lighting battery packs can cause LEDs to flicker when lighting fixtures change between brightness levels, due to battery packs not being able to keep up with the demand placed on them. One of the main reasons for this issue is transient voltage sag.

Professional LED fixtures have several factors that affect voltage stability including internal resistance, discharge current, type of electrical connections, BMS (battery management system) protection thresholds and compatibility with LED drivers. Recognizing and understanding these factors will allow us to design a Stage Lighting Battery Pack with the performance and power to provide more sophisticated and complex lighting effects.

Why Does Voltage Drop Occur in a Stage Lighting Battery Pack?

Battery voltage under load drops for several reasons. Three of these reasons are:

• Cell Internal Resistance (DCIR): Falls as discharge current increases. DCIR increases with battery aging and is often more pronounced at lower temperatures.

• Transient Load Current: In constant current applications (e.g., LED Drivers) if the lighting effect demands a sudden increase in current, the battery cell can experience a transient load and additional voltage sag can occur.

Total Circuit Resistance

Nickel Strips, welded joints, cables, connectors, and BMS MOSFETs contribute to the overall resistance of the circuit. Total resistance can be described by the equation:

ΔV = I × Rtotal

Approximately, 0.15 Ω of circuit resistance results in a voltage drop of 1.2V across the resistance and 9.6W of resistive heat loss.

These are representative values and not specifications for any GLOFLUX products. Battery resistance is a function of temperature and state of charge (SOC).

Due to this variability, it is recommended that for stage lighting, the battery pack selection be based upon the discharge characteristics of the batteries rather than the pack's nominal capacity.

How Does Battery Voltage Sag Cause LED Flickering?

Professional LED lighting systems use constant-current drivers to regulate LED output. Battery voltage sag pushes the driver into undervoltage protection, which results in the LED lighting system turning off. Additionally, battery voltage sag may cause the driver to disrupt current regulation and turn off the lighting system.

Battery-Related Flicker vs Driver-Related Flicker

Failure Mechanism	Electrical Behavior	Typical Symptom
Battery voltage sag	Input voltage falls under peak load	Dimming or fixture reset
BMS protection trip	Discharge circuit disconnects	Sudden blackout
Driver output ripple	LED current fluctuates	Periodic brightness variation
PWM dimming	LEDs switch at modulation frequency	Visible flicker or camera banding
DMX control fault	Incorrect brightness commands	Irregular lighting changes

A Stage Lighting Battery Pack can't reduce flicker due to PWM frequency and/or instability of LED drivers.

Accurate diagnosis requires monitoring battery voltage, driver input and optical output at the same time.

How to Design a Stage Lighting Battery Pack for Stable Power

12S2P and Voltage Architecture

We use a 12S2P configuration in our 18650 lithium battery platforms to offer compatible LED stage lighting and portable audio equipment, with a nominal voltage of 44.4V.

It consists of:

• 12 Series-connected cells to establish the nominal voltage of the battery pack.

• Two cells in parallel in each group to increase capacity and reduce discharge current of each cell.

• 50.4V maximum charging voltage to require a charging circuit compatible with the battery pack.

• Wiring and connectors customizable to suit application to facilitate electrical integration.

• Given a power demand, decreasing the supply voltage would increase the current and corresponding I²R losses in wiring.

It will also need to be able to handle the full range of the battery voltage, not just the nominal 44.4V.

Discharge Capability and BMS Coordination

A reliable Stage Lighting Battery Pack needs the ability to provide the continuous current requested by the load and to provide a substantial safety margin for the transient currents.

Specifications for the battery should include:

• Continuous discharge current at the operating temperature.

• Peak current and its duration and frequency of occurrence.

• The overcurrent protection threshold and protection time delay of the BMS.

• Cell undervoltage cutoff.

• Driver minimum input voltage.

• Thermal protection, cell balancing, and charger compatibility.

Protection settings should be configured to provide full protection during typical operation.

How GLOFLUX Manufacturing Precision Supports Voltage Consistency

Battery pack assembly can influence the degree of voltage consistency within a multi-cell pack. In a 12S2P configuration, a large difference between the individual cells can lead to uneven current sharing and decreased capacity as well as reduced voltage limits for the cell groups.

At GLOFLUX, our cylindrical battery engineering process describes the following manufacturing controls:

Manufacturing Control	GLOFLUX Published Reference	Engineering Significance
Cell capacity matching	±1%	Limits capacity variation between selected cells
Internal resistance matching	±2mΩ	Reduces resistance mismatch and uneven current sharing
Weld connection resistance	Below 0.5mΩ	Limits localized voltage loss and resistive heating
Quality inspection	60+ checkpoints	Covers material selection, assembly, and verification

These figures are process references, not guaranteed tolerances for every Stage Lighting Battery Pack configuration.

Our manufacturing approach combines cell grading, resistance welding, insulation control, BMS integration, and electrical inspection. For OEM projects, acceptance limits should be confirmed using the approved battery specification and production test records.

Comparing Engineering Solutions for Voltage Stability

Design Approach	Primary Benefit	Design Consideration
Low-DCIR cells	Lower voltage sag	Capacity, cost, and thermal trade-offs
Higher-voltage architecture	Lower current at equal power	Driver input compatibility
Larger wire cross-section	Reduced cable resistance	Weight and installation space
Low-resistance connectors	Lower contact losses	Vibration and mating-cycle durability
Correctly rated BMS	Reliable load protection	Peak-current timing and cutoff behavior
Regulated LED driver	Stable LED current	Efficiency and input-voltage limits

No individual measure guarantees stable operation. The complete Stage Lighting Battery Pack and LED driver must be evaluated as one electrical system.

How to Test Voltage Stability Under Real Stage Loads

Constant-current discharge tests are not good at determining how quickly a battery can provide power.

Recommended Electrical Validation

Dynamic Load Testing: Apply synchronous loads and levels of interest. Record voltage sag over time.

Voltage Measurement: Measure battery terminal voltage, driver input voltage, and anywhere else voltage loss is of interest. Determine voltage loss through wiring and connectors.

Thermal Testing: Measure the temperatures of the cells, BMS and connectors and take into consideration the environmental limits of interest.

SOC and Aging Testing: Conduct load profiles at low state of charge and after charge/discharge cycling to represent the aging of the battery.

Flicker Verification: Measure the optical output, driver current and/or PWM and battery voltage to look for correspondence with respect to the brightness level of interest.

For outdoor fixtures, degradation of connectors due to vibration and moisture should be tested as well.

OEM Selection: What Should Manufacturers Verify?

Before approving a Stage Lighting Battery Pack, OEM buyers should verify the following:

Cell configuration and DCIR.

Continuous and peak current ratings and the conditions under which the tests were performed.

BMS protection parameters.

Cable and connector specifications and drawings.

Safety and UN documentation.

The specified parameters should reflect the final configuration and not an unrelated battery.

GLOFLUX Custom Stage Lighting Battery Packs

GLOFLUX helps develop custom cell and battery pack configurations for OEM/ODM clients.

Our 18650 12S2P battery pack offers a reference platform for manufacturing portable stage lighting systems.

For more information about our battery packs and to provide your voltage and load requirements to our engineers, visit our website.

FAQs

Q1. What Stage Lighting Battery Pack does GLOFLUX offer?

GLOFLUX offers a 44.4V lithium-ion battery pack using 18650 cells in a 12S2P configuration for compatible LED stage lighting systems.

Q2. How does GLOFLUX's 12S2P battery design support stable power?

Twelve series groups provide nominal voltage, while two parallel cells per group share current. Stability also depends on cell resistance and load conditions.

Q3. Can GLOFLUX's Stage Lighting Battery Pack prevent LED flickering?

Proper battery matching can reduce voltage-sag-related flicker. PWM, DMX, and LED driver faults require separate diagnosis.

Q4. What charging voltage does GLOFLUX's 44.4V battery pack require?

The published maximum charging voltage is 50.4V. The charger must match the battery chemistry, configuration, and approved charging specifications.

Q5. Can GLOFLUX customize BMS protection for stage lighting?

Yes. GLOFLUX supports customized protection circuits, with current limits and protection thresholds specified for the application.