Dimethyl carbonate (DMC) plays a critical role in lithium-ion battery electrolytes, where solvent purity directly impacts performance, safety, and lifetime. Even trace-level impurities can contribute to degradation of solid electrolyte interfaces, consumption of lithium ions, or gas formation—effects that compromise both efficiency and safety.As battery materials continue to evolve, analytical approaches must provide both high sensitivity and high-confidence identification. A recent LECO application study demonstrates how combining two GC-MS platforms enables a more complete characterization of DMC impurities than either approach alone.<h3>Why Impurity Characterization in DMC Is Challenging</h3>Battery-grade solvents demand detection of contaminants across a wide concentration range, starting from major byproducts to trace-level species. In DMC, impurities may include oxygenated compounds, hydrocarbons, and nitriles, many of which arise from synthesis or handling processes.These compounds can co-elute or exist at levels below typical detection thresholds, making comprehensive analysis difficult with a single analytical technique. In addition, electron ionization (EI) spectra do not always provide a clear molecular ion, complicating compound confirmation.<h3>A Complementary Analytical Strategy: Sensitivity + Confidence</h3>The application note demonstrates a combined workflow using the approach:<ul><li><a target="_blank" rel="noopener noreferrer" href="https://gcms.labrulez.com/products/1097">Pegasus BTX (GC-TOFMS)</a>&nbsp;for high-sensitivity detection</li><li><a target="_blank" rel="noopener noreferrer" href="https://gcms.labrulez.com/products/38">Pegasus HRT (high-resolution GC-MS)</a>&nbsp;for accurate mass confirmation</li></ul>The Pegasus BTX enables detection of impurities at below parts-per-billion levels, ensuring that even low-abundance analytes are captured.Following detection, the Pegasus HRT provides high-resolution, accurate mass data in both EI and positive chemical ionization (PCI) modes. PCI is particularly valuable when EI spectra lack a clear molecular ion, allowing confirmation through common adduct species such as protonated molecular ions [M+H]⁺.Because both ionization modes can be accessed without hardware changes, the workflow supports efficient, multi-dimensional confirmation of analyte identity.<h3>Observations</h3>Using this combined approach, multiple classes of impurities were identified in the DMC sample. These included:<ul><li>Oxygenated reaction byproducts</li><li>Alcohols, carbonates, and ethers</li><li>Hydrocarbons and aromatic species</li><li>Additional low-level analytes detected with high library match scores</li></ul>Importantly, the high sensitivity of the Pegasus BTX revealed a broader set of low-concentration compounds, while the Pegasus HRT increased confidence in compound identification through accurate mass measurements and confirmation of molecular formulas. &nbsp;The study also highlights cases where co-eluting compounds were successfully deconvoluted, allowing individual components to be identified even without complete chromatographic separation.<h3>Why This Matters for Battery Materials Analysis</h3>This work illustrates a key principle for advanced materials characterization: detection and identification are distinct challenges that often require complementary solutions.<ul><li>Detection alone&nbsp;is insufficient without confident identification</li><li>High-resolution confirmation&nbsp;is limited if low-level species are not first detected</li></ul>By combining these capabilities, laboratories can gain deeper insight into solvent purity, production processes, and potential performance risks in battery systems.<h3>Explore the Complete Study</h3>This short overview highlights only a portion of the findings. The full application note provides:<ul><li>Detailed acquisition parameters and workflows</li><li>Chromatographic and spectral data examples</li><li>Confirmed impurity lists with retention times and similarity scores</li><li>Examples demonstrating EI/PCI complementarity and accurate mass confirmation</li></ul>To better understand how complementary GC-MS techniques can improve confidence in battery solvent analysis, download the full application note: <a target="_blank" rel="noopener noreferrer" href="https://www.leco.com/documents/203-821-731/">“Battery Solvent Characterization: Identifying Impurities in Dimethyl Carbonate”.</a>

 Confident Identification of Battery Solvent Impurities Using Complementary GC-MS Techniques

The international standard ISO/IEC 17025 [1] clause 7.7.2 with regards to ensuring the validity of results, requires a laboratory to participate in proficiency testing (PT) and/or to participate in interlaboratory comparisons (ILCs) other than PT. However, no guidance as to what these other ILCs might be, or indeed how they might compare in relation to PT, is provided. This leaflet aims to outline other ILCs available, pointing out some of the limitations as compared to PT.&nbsp;There are three major types of ILCs in which a group of laboratories analyses identical portions from a homogeneous, stable test sample, with each type being characterized by its intended purpose [2,3]:<img src="https://storage.googleapis.com/labrulez-bucket-strapi-h3hsga3/Eurachem_Interlaboratory_comparisons_other_than_proficiency_testing_2_d9263807fb.jpg" alt="Eurachem: Interlaboratory comparisons other than proficiency testing" srcset="https://storage.googleapis.com/labrulez-bucket-strapi-h3hsga3/thumbnail_Eurachem_Interlaboratory_comparisons_other_than_proficiency_testing_2_d9263807fb.jpg 245w," sizes="100vw" width="1507" height="607">A key point is that PT is an ILC that is designed to specifically evaluate the performance of participants, providing them with an infrastructure to monitor and assess the validity of their results. This is not the key purpose of the two other ILCs, and thus depending on their intended purpose they have a number of limitations that laboratories need to be aware of when using them rather than PT. Only proficiency testing should have been conducted in full compliance to the competency standard ISO/IEC 17043 [4].&nbsp;<h4>Evaluation of measurement procedure performance&nbsp;</h4>These ILCs, are designed to assess how a particular measurement procedure performs and whether it is fit for its intended purpose. These ILCs are often referred to as a ‘method performance study’ or a ‘collaborative study’ [2]. Some limitations of using such ILCs for monitoring laboratory performance as an alternative to PT are:&nbsp;<ul><li>All participants use the same measurement procedure i.e. the measurement procedure that is being validated. Unless the measurement procedure is being routinely used by the participating laboratory such an ILC will not assess the routine performance of the laboratory using their own routine measurement procedure. Nor does it enable them to compare their performance with other laboratories using alternative measurement procedures.&nbsp;</li><li>The measurement procedure is likely to be new, so participants may not have established stable procedures and quality control, so performance may not reflect routine use.&nbsp;</li><li>The report from such an ILC would not provide information on the performance of the participant, if the statistical model used makes the assumption that all laboratories perform with equal variability.</li><li>The design of the study may require the participants to assess multiple samples and/or to undertake multiple replicate analysis on the test materials. This may not be representative of the routine measurements or tests undertaken by the laboratory.&nbsp;</li><li>The conclusion of the ILC might be that the measurement procedure being assessed is not valid.&nbsp;</li></ul><img src="https://storage.googleapis.com/labrulez-bucket-strapi-h3hsga3/Eurachem_Interlaboratory_comparisons_other_than_proficiency_testing_3_a53ecd2f5d.jpg" alt="Eurachem: Interlaboratory comparisons other than proficiency testing" srcset="https://storage.googleapis.com/labrulez-bucket-strapi-h3hsga3/thumbnail_Eurachem_Interlaboratory_comparisons_other_than_proficiency_testing_3_a53ecd2f5d.jpg 157w," sizes="100vw" width="570" height="566"><h4>Characterisation of candidate reference materials&nbsp;</h4>These are ILCs that assign a property value to a candidate reference material, usually with a stated measurement uncertainty. These are often referred to as a ‘material certification study’ [2]. Limitations of using such ILCs as an alternative to PT are:&nbsp;<ul><li>The analysis of the candidate reference material is likely to require additional care in exercising the routine measurement procedure, such as substantially more replication, and/or may require quite different reporting formats (e.g. all valid replicates instead of a mean result). Thus, such an ILC will not necessarily provide an evaluation of the performance of the laboratory based on the routine use of their measurement procedures.&nbsp;</li><li>The report from such an ILC may include the results from the participating laboratories but would not provide information on the performance of each laboratory.&nbsp;</li><li>Participating laboratories may be required to assess multiple samples and/or to undertake multiple replicate analysis on the candidate reference materials. Thus this may not be representative of the routine measurements or tests undertaken by the laboratory.&nbsp;</li></ul><h4>Other ILCs&nbsp;</h4>Some other ILCs, whilst not being conducted in full compliance of the requirements of ISO/IEC 17043, may be designed to evaluate participant performance. These would include small ILCs as defined by EA‑2/21 [5] or split sample ILCs i.e. where a portion of a single sample is sent to two or three laboratories. Whilst these ILCs are specifically designed to evaluate participant performance, they may not provide a comprehensive comparison that a PT might provide. In such cases the laboratory needs to evaluate carefully the competence of the organization managing the ILC and the suitability of the service externally provided (ISO/IEC 17025 clause 6.6).

Interlaboratory comparisons other than proficiency testing

RI Calibration in NIST26 Chromatogram and Applying to Calculating RI in Samples

Article

Product

Application

Academy

Video

Software

Eurachem is a European network promoting international traceability of chemical measurements and good analytical practice. It provides expert guidance, supports method validation, uncertainty evaluation, proficiency testing, and facilitates discussion on technical and policy issues in analytical quality.

Eurachem

In 1936, the Laboratory Equipment Company introduced the first rapid carbon determinator for the American iron and steel industry.  Today, almost 80 years later, LECO is recognized globally as a leader in the development of high-quality analytical instrumentation, mass spectrometers, comprehensive two-dimensional chromatography, metallography & optical equipment as well as consumables.

LECO

My main interest is the identification of organic compounds by mass spectrometry in organic mixtures.

James Little/Mass Spec Interpretation Services

Wasson Pressurized Liquid Auto-sampler (LS100B)

Wasson-ECE Liquid Auto-Sampler (LS100B) offers laboratory automation for pressurized liquid samples such as liquefied petroleum gas (LPG) and natural gas liquids (NGL).

Wasson-ECE Liquid Auto-Sampler (LS100B) offers laboratory automation for pressurized liquid samples such as liquefied petroleum gas (LPG) and natural gas liquids (NGL).
The LS100B uses inert gases to maintain pressure so that the sample remains in the liquid state at ambient temperature as it passes to the GC for analysis.
The LS100B accommodates up to nine sample cylinders with 1/4 inch tube, VCO, or quick connect fittings. These fittings hold the sample cylinders vertically, ensuring that samples are drawn from the bottom of the cylinder.
<h4>Pressurized Liquid Auto-sampler Features</h4>
<ul>
<li>Purges automatically with carrier gas between each sample run
</li>
<li>Remote-starts the GC and the data recording software such as ChemStation™
</li>
<li>Adds a date/time stamp to all samples
</li>
<li>Holds up to nine 3.5 inch / 8.9 cm diameter sample cylinders
</li>
<li>Works with standard open or floating-piston sample cylinders
</li>
<li>Pauses automatically when it detects that the GC is not running or not ready
</li>
<li>Can interrupt the scheduled sample sequence to process a priority sample
</li>
</ul>

Wasson Dynamic Blender for GC (DB302)

The Dynamic Blender is a portable gas blending device that dilutes a sample or a certified standard with a matrix gas of choice.

Gas chromatography (GC) analyses often include trace level detection of components requiring samples or standards at low concentrations. Some analytes are expensive or difficult to purchase at low levels due to reactivity, adsorption, or high molecular weight. Analyses may also cover a wide concentration range, requiring multi-point calibration.
The Wasson-ECE Dynamic Blender (DB302) provides a simple solution to these calibration needs. The Dynamic Blender is a portable gas blending device that dilutes a sample or a certified standard with a matrix gas of choice. One certified standard with concentrations at the upper limit of the desired calibration curve can be diluted to a lower level (&gt;2 orders of magnitude lower) to create a full calibration curve.
An inert flow path and heated bridge eliminate adsorption and condensation problems when blending gas standards that include sulfur, nitrogen, and other reactive compounds.
An on-board flow controller allows the diluent gas flow to be controlled digitally and samples are fed directly to a gas chromatograph. The Dynamic Blender eliminates the need to purchase and store multiple gas cylinders and provides an easy, cost-effective solution for gas phase calibration needs.
<h4>Dynamic Blender Features</h4>
<ul>
<li>Approximately 100 pre-programmed pure diluent gases and mixtures and twenty user configurable diluent mixture slots.
</li>
<li>Maximum Diluent Pressure of 100 psi (leak tested to this pressure)
</li>
<li>Maximum Temperature of 150°C (operation verified at this temp.)
</li>
<li>Mass Flow Controller Range of 10 – 500 cc/min
</li>
<li>7 μm in-line gas filters (treated) are also provided
</li>
<li>Specially passivated tubing for trace reactive compounds (sulfurs, oxygenates, etc.)
</li>
</ul>
*This treatment is not suitable for samples with pH &gt; 8.0, so please notify your sales representative if you have high pH samples.

Wasson Variable Pressure Sampler (VPS)

The Variable Pressure Sampler (VPS) works in two ways to ensure the precision and accuracy of gas results.

The Variable Pressure Sampler (VPS) works in two ways to ensure the precision and accuracy of gas results. The first method is pressure correction, used to create uniform pressure among all injected samples and the calibration blend. The second method is multi-point calibration, which can deliver a calibration blend to the GC at various pressures.
The VPS pressure correction system performs a multi-step process that ensures samples and calibration blends are at uniform pressures when they are injected.
First, when the calibration blend is run through the GC, the VPS measures and stores the pressure of the calibration blend at the time of injection. Then, as each sample is injected at the stored pressure, the VPS adjusts the pressure of the sample to match the pressure of the calibration blend.
The inject pressure of the sample is reported to Agilent Technologies OpenLAB ChemStation software so calculations and quality control operations can be performed.
Using the VPS, calibration samples can be run at various pressures from a single standard. This decreases overall lab costs while ensuring greater accuracy in results. The multi-point calibration function allows testing for signal linearity at different pressures. With this feature, the user can easily pinpoint the range of pressures which generates the most accurate and meaningful results from the calibration standard.
<img src="https://storage.googleapis.com/labrulez-bucket-strapi-h3hsga3/Wassson_Variable_Pressure_Sampler_VPS_linearity_77314725d6.jpg" alt="Wassson: Variable Pressure Sampler (VPS) - linearity"/>

Wasson LPG Vaporizer (1107)

The LPG Vaporizer uses an innovative, proprietary technique to vaporize liquid samples for injection in an existing GC system.

The LPG Vaporizer uses an innovative, proprietary technique to vaporize liquid samples for injection in an existing GC system. This convenient laboratory system offers flexibility and accuracy for both gas and liquid samples.
The LPG Vaporizer is more convenient than a typical liquid sample valve with more accurate results. All liquid samples are vaporized and run at a constant pressure, eliminating sample density changes that cause errors in liquid phase samples. This ensures sharp, easy-to-read peaks for all samples.
The LPG Vaporizer is built with specially passivated parts for analyzing trace reactive analytes such as sulfurs and oxygenates.
Wasson-ECE&#39;s unique, proprietary vaporization technique produces an even and accurate gas sample. Other vaporizers use tubing with a large volume, causing samples to fractionate when vaporized. This can lead to incomplete sample analysis. The LPG Vaporizer controls the injection volume so that all elements in the liquid sample are vaporized and sent to the GC simultaneously, producing a complete and accurate analysis of the sample.
<h4>LPG Vaporizer Features</h4>
<ul>
<li>Inject liquid and gas samples with a single valve
</li>
<li>High sample throughput
</li>
<li>Purging technique reduces cross-contamination
</li>
<li>Ability to stop sample flow to the GC at any time
</li>
<li>Controlled injection volume
</li>
<li>4 ft. heated bridge from vaporizer to customer&#39;s GC sample valve to prevent sample re-condensing
</li>
</ul>

Wasson Gas Auto-sampler (AS202)

The Gas Auto-sampler (AS202) is a stand-alone device that delivers samples to the GC through a heated bridge, ensuring that samples are injected at the appropriate temperature.

The Gas Auto-sampler (AS202) is a stand-alone device that delivers samples to the GC through a heated bridge, ensuring that samples are injected at the appropriate temperature. The heated pathway is purged with carrier gas between each sample injection, and a vacuum pump ensures an extremely low level of matrix cross-contamination (typically less than 50 ppm).
Samples are loaded into the AS202 oven, which can hold up to twelve 500cc sample cylinders or nine 1L cylinders. The shelves are removable and adjustable and can also be tilted to prevent injection of any residual liquids which then changes the setup to allow for a maximum of eight 500cc or six 1L cylinders.
Samples (1000 psig / 6895 kPa max) are automatically regulated during the purging sequence so the GC injects all samples and calibration blends at atmospheric pressure. The AS202 can also be configured to automate injection of samples that are already at atmospheric pressure.
The table below compares the GC analysis results for 2 mL samples of n-pentane and n-hexane at 100 psig in propane. In the first trial, the sample is sent to the GC from the AS202 at ambient temperature; in the second trial the AS202 heats the samples to 130°C before injection.
<img src="https://storage.googleapis.com/labrulez-bucket-strapi-h3hsga3/Wasson_Wasson_autosampler_pro_plynne_vzorky_Srovnani_vysledku_GC_analyz_f7c0ad0991.jpg" alt="Wasson: Repeatability Comparisons - Heated vs. Unheated"/>

Products from category Sample injection from Wasson-ECE Instrumentation - page 1

Related content

RI Calibration in NIST26 Chromatogram and Applying to Calculating RI in Samples

Interlaboratory comparisons other than proficiency testing

Confident Identification of Battery Solvent Impurities Using Complementary GC-MS Techniques