Automated environmental-chamber battery cycler

BATTERIES 2026-06-10

An automated test setup for cycling battery strings inside a thermally-controlled, insulated chamber — built to study cell performance across temperature under realistic, hard duty cycles.

The cell-holder structure carries 6 strings of 7 cells in parallel (42 holders), each holder fitted with high-current, spring-loaded Kelvin (4-wire) pin contacts so the current and voltage-sense paths stay separate — voltage is measured at the cell, not across the harness. Every holder is individually sensed.

Cell-holder structure receiving its balanced wiring harnesses — FIG. 01 — Cell-holder array during harnessing.

Second view of the cell-holder structure and wiring harnesses — FIG. 02 — Six strings × seven parallel cells, individually sensed.

The power harnesses are built as length- and resistance-matched pairs, so charge and voltage distribute evenly across the parallel cells even during very hard cycles. Power distribution runs through Amass XT120 connectors.

Wiring close-up with the heater-blowers visible behind — FIG. 03 — Harness wiring; heater-blowers visible at the rear.

The whole assembly sits inside a thermally insulated chamber before being connected out to the external cyclers.

Assembly inside the thermally insulated chamber — FIG. 04 — Assembly in the insulated chamber, prior to final connection.

Heating is handled by the internal heater-blowers. An empty test run confirmed the chamber’s heating capability, reaching 92.8 °C:

Multimeter reading 92.8 °C during an empty heating test — FIG. 05 — Empty-chamber heating test, 92.8 °C at the cell holders.

Internal temperatures are cross-checked with a thermal camera:

Thermal-camera view of the chamber interior — FIG. 06 — Thermal-camera readout of the chamber interior.

Second thermal-camera still of the interior temperatures — FIG. 07 — Interior temperature distribution.

FIG. 08 — Thermal-camera walkthrough of the chamber interior (video).

Topology	6 strings × 7 parallel cells (42 holders)
Contacts	High-current spring-loaded Kelvin (4-wire) pins
Sensing	Per-cell-holder voltage; thermal-camera cross-check
Harnessing	Length- & resistance-matched pairs for balanced distribution
Power connector	Amass XT120
Thermal	Insulated chamber, internal heater-blowers (verified to 92.8 °C)

In use, with cells loaded and the chamber closed:

Chamber in use with cells loaded — FIG. 09 — Chamber closed and running under load.

Cells loaded into the chamber, second view — FIG. 10 — Loaded cell-holder array.

Cells loaded into the chamber, third view — FIG. 11 — Cycling under controlled temperature.