BU-923: Getting Deep Cycle Batteries Mission Ready

The battery is the weakest link in a chain that causes half of all system failures. Battery diagnostics has been lagging, but technology is available that observes capacity fade to fully use each battery with call to replace before failure.

Spectro™ battery rapid-testers by Cadex model a battery against a matrix to secure Minimum Operational Reserve Energy (MORE) based on capacity, the leading health indicator.

Screenshot 2026 04 10 131314 — Deep-cycle batteries serve a wide range of applications

Threshold Setting

Capacity pass/fail levels for deep-cycle batteries are commonly set to 60%. A PASS assures a full day service; FAIL calls for replacement or lower tasks.

The Spectro devices come with a matrix of choice and ability to download other matrices from the Matrix Library. The matrices are kept in the CadexCloud, a web app that also stores test results and shares data with fleet supervisors.

How does Spectro™ work?

A frequency scan produces a Nyquist plot that models a battery against a matrix to extract capacity, state-of-charge (SoC) and other characteristics. The test is non-invasive and accuracy rests on the Matrix Integrity Level (MIL) that can be improved by scanning additional batteries of same-model but with diverse performances to capture all anomalies.

The EIS Direct-Drive tests batteries in 30 seconds with capacities of up to 300Ah. The battery is not agitated during testing and the compact test unit stays cool. Scientists predict that battery diagnostics will advance to Multi-Model EIS methods, a patented technology Spectro devices use.

Checking Battery Match

Battery runtime is governed by the weakest link in a chain. Matching can be assured by measuring leftover charge of each pack after service with the Spectro CM-24. State-of-charge of a well-matched string should be within 10%. Replace low performers with a pack of similar capacity

Screenshot 2026 04 10 142108 — *Identifying weakest link by measuring remaining charge after service*

Operation

Settings are entered through the host with test results shown in numbers and by graphics. The system works in local mode by storing test data in the host with optional connection to CadexCloud to share test results with fleet supervisors.

Saved data includes battery status, charge levels, internal battery resistance and temperature, as well as VIN records and work orders. Compatible printers produce print reports and labels.

Historic Test Data

Testing is simplified by marking each battery with QR code. A scan connects the host to CadexCloud to download custom matrices, view previous results and store new radings.

Picture3a — *Viewing battery history by QR code*

With matrices available from the Matrix library, Spectro devices form an open test platform to service all major batteries.

Capacity Thresholds

Pass/fail settings can be changed by selecting matrices with different MORE thresholds. This enables reserving top performers for critical uses while keeping regular packs for everyday uses.

Spectro™ Characteristics

Battery rapid-testing with multi-model electrochemical impedance spectroscopy using frequency scanning with AI analysis delivers impressing results. Typical scanning frequencies range from 2,000Hz to 4Hz for most batteries with option to go lower if time allows. Common test voltages are 3V to 48V with capacity assessment of up to 300Ah provided the internal battery resistance is above 300µΩ.

Last Updated: 10-Apr-2026

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Batteries In A Portable World

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