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arxiv: 1906.11087 · v1 · pith:JK7AD5GGnew · submitted 2019-06-26 · ⚛️ physics.app-ph · cond-mat.mtrl-sci

Intermixed Cation-Anion Aqueous Battery Based on an Extremely Fast and Long-Cycling Di-Block Bipyridinium-Naphthalene Diimide Oligomer

Sofia Perticarari , Tom Doizy , Patrick Soudan , Chris Ewels , Camille Latouche , Dominique Guyomard , Fabrice Odobel , Philippe Poizot
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Joel Gaubicher
This is my paper

Pith reviewed 2026-05-25 15:02 UTC · model grok-4.3

classification ⚛️ physics.app-ph cond-mat.mtrl-sci
keywords aqueous batteryorganic electrodedi-block oligomercation-anion exchangeneutral electrolytelong-term cyclingocean waterenergy storage
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The pith

A di-block oligomer enables simultaneous cation-anion exchange in an aqueous battery, delivering 105 mAh/g capacity with 6500-cycle stability in neutral electrolytes including ocean water.

A machine-rendered reading of the paper's core claim, the machinery that carries it, and where it could break.

This paper introduces a novel di-block oligomer called DNVBr as the negative electrode in an all-organic aqueous battery that operates at neutral pH. The central feature is an intermixed p/n-type storage mechanism that permits the simultaneous exchange of Na+, Mg2+, and Cl- ions from the electrolyte. This setup is claimed to produce up to 105 mAh/g specific capacity along with retention over 6500 cycles in neutral solutions, including raw ocean water for roughly 3000 cycles. The oligomer exhibits fast kinetics that support nearly 60 mAh/g without any conducting additives and areal capacities of 3.4 mAh/cm2 at C rate. A full cell using a commercial TEMPO positive electrode reaches about 40 Wh/kg energy density over 1600 cycles in an inexpensive self-pH-buffered electrolyte.

Core claim

The di-block bipyridinium-naphthalene diimide oligomer DNVBr serves as a negative electrode material whose intermixed p/n-type storage mechanism enables simultaneous exchange of Na+, Mg2+, and Cl- ions, yielding up to 105 mAh/g capacity, retention over 6500 cycles in neutral media including ocean water, unmatched capacities without additives, and full-cell performance near 40 Wh/kg at C-rate.

What carries the argument

The di-block oligomer DNVBr and its intermixed p/n-type storage mechanism for simultaneous cation-anion exchange.

If this is right

  • The battery operates in raw ocean water for about 3000 cycles spanning 75 days.
  • Specific capacity reaches near 60 mAh/g electrode without any conducting additives.
  • Areal capacity attains 3.4 mAh/cm2 at C rate.
  • Full cell pairing with commercial TEMPO molecule sustains over 1600 cycles.
  • Energy density approaches 40 Wh/kg materials at C rate in inexpensive self-pH-buffered electrolyte.

Where Pith is reading between the lines

These are editorial extensions of the paper, not claims the author makes directly.

  • The simultaneous ion-exchange approach could guide synthesis of related organic oligomers for other aqueous battery chemistries.
  • Direct use of ions abundant in seawater points toward stationary storage systems that integrate with natural water sources.
  • High rate performance without carbon additives may lower manufacturing complexity for grid-scale applications.
  • Varying the block lengths or monomer ratios offers a route to test further gains in capacity or cycle life.

Load-bearing premise

The claim rests on the premise that the intermixed p/n-type storage mechanism in the di-block oligomer directly causes the high capacity and cycling stability without major side reactions or degradation.

What would settle it

Electrochemical measurements that detect no simultaneous cation and anion exchange, or capacity retention falling below 80 percent after a few hundred cycles in neutral electrolyte, would undermine the performance claims.

Figures

Figures reproduced from arXiv: 1906.11087 by Camille Latouche, Chris Ewels, Dominique Guyomard, Fabrice Odobel, Joel Gaubicher, Patrick Soudan, Philippe Poizot, Sofia Perticarari, Tom Doizy.

Figure 4
Figure 4. Figure 4: Calculated LDA-DFT Kohn-Sham eigenvalues (eV) for an isolated DNV molecule, showing the real￾space wave function distribution on the molecule for states at the Fermi level. Level offset is for visual clarity and does not represent symmetry equivalent states. The molecule is in the neutral charge state, i.e. after charge transfer from nominal counter-anions, which are not included explicitly in the calculat… view at source ↗
Figure 5
Figure 5. Figure 5: (a) Capacity retentions on charge (oxidation of the material) for (violet) DNVBr and (light blue) MNV composite electrodes in NaClO4 2.5 M according to the standard cycling protocol (see experimental section). The red curve is associated with the capacity retention of DNVBr using a modified standard protocol (see experimental section) within −0.85 ≤ E ≤ 0 V as potential window and current loads as specifie… view at source ↗
Figure 7
Figure 7. Figure 7: Capacity retention on charge (oxidation of the material) and corresponding Coulombic efficiency curves for DNVBr composite electrodes in (a) NaClO4 2.5 M and (b) ocean water. In conclusion, by comparison to conventional inorganic and organic materials previously reported, several unique advantages can be gleaned from the specific molecular structure of DNV. Indeed, (i) NDI brings both a high hydrophobicity… view at source ↗
read the original abstract

Aqueous batteries, particularly those integrating organic active materials functioning in a neutral pH environment, stand out as highly promising contenders in the stationary electrochemical storage domain, owing to their unparalleled safety, sustainability and low-cost materials. Herein, a novel di-block oligomer (DNVBr), serving as the negative electrode of an all-organic aqueous battery, is shown to offer exceptional output capabilities. The battery's performance is further enhanced by a unique intermixed p/n-type storage mechanism, which is able to simultaneously exchange light and naturally abundant Na+, Mg2+ and Cl-. Reaching up to 105 mAh/g, this system shows remarkable capacity retention for several thousand cycles (6500 cycles, ~40 days) in various neutral electrolytes, including raw ocean water (~3000 cycles, ~75 days). The surprisingly fast kinetics of this di-block oligomer allow to attain an unmatched specific capacity of near to 60mAh/g electrode while entirely devoid of conducting additives, and more than 80mAh/g electrode with 10% carbon additive, as well as displaying an areal capacity as high as 3.4mAh/cm2 at C rate. Full cell validation was demonstrated over 1600 cycles by virtue of a commercial TEMPO molecule, which permitted an energy density of close to 40Wh/kgmaterials at C rate in a self-pH-buffered and inexpensive aqueous electrolyte.

Editorial analysis

A structured set of objections, weighed in public.

Desk editor's note, referee report, simulated authors' rebuttal, and a circularity audit. Tearing a paper down is the easy half of reading it; the pith above is the substance, this is the friction.

Referee Report

2 major / 1 minor

Summary. The manuscript introduces a novel di-block oligomer (DNVBr) as the negative electrode in an all-organic aqueous battery. It claims exceptional performance metrics including up to 105 mAh/g specific capacity, retention over 6500 cycles (~40 days) in neutral electrolytes including raw ocean water (~3000 cycles), unmatched specific capacity near 60 mAh/g without conducting additives (or >80 mAh/g with 10% carbon), areal capacity of 3.4 mAh/cm² at C-rate, and full-cell validation over 1600 cycles yielding ~40 Wh/kg at C-rate in a self-pH-buffered electrolyte. These are attributed to a unique intermixed p/n-type storage mechanism enabling simultaneous Na+/Mg2+/Cl- exchange.

Significance. If the reported performance and stability hold under rigorous validation, the work would be significant for advancing safe, low-cost, neutral-pH aqueous organic batteries for stationary storage, particularly through additive-free operation and compatibility with seawater electrolytes. The di-block design and multi-ion mechanism, if mechanistically substantiated, could inform design of high-kinetics organic electrodes.

major comments (2)
  1. [Abstract and Results] Abstract and electrochemical results sections: Specific performance claims (105 mAh/g, 6500 cycles, 60 mAh/g without additives, 3.4 mAh/cm²) are presented without error bars, replicate counts, explicit measurement protocols, or data exclusion criteria. This undermines assessment of whether the data support the headline numbers, as noted in the absence of these details even in the full text's standard CV/galvanostatic/EIS reporting.
  2. [Mechanism discussion] Mechanism and performance attribution sections: The central claim that the di-block architecture enables an 'intermixed p/n-type storage mechanism' responsible for the high capacity, fast kinetics, and long cycling (including in ocean water) is not supported by a load-bearing control experiment. No comparison to physical mixtures of the individual bipyridinium and naphthalene diimide units or mono-block analogs is provided to isolate the di-block contribution, nor is there direct real-time evidence (beyond standard post-mortem SEM/FTIR and EIS) for simultaneous multi-ion exchange without side reactions.
minor comments (1)
  1. [Abstract] Abstract: Minor phrasing issues such as 'near to 60mAh/g' and inconsistent spacing in units (e.g., '40Wh/kgmaterials') should be standardized for clarity.

Simulated Author's Rebuttal

2 responses · 0 unresolved

We thank the referee for the constructive feedback on our manuscript. We address each major comment below and indicate the revisions planned for the next version.

read point-by-point responses

  1. Referee: [Abstract and Results] Abstract and electrochemical results sections: Specific performance claims (105 mAh/g, 6500 cycles, 60 mAh/g without additives, 3.4 mAh/cm²) are presented without error bars, replicate counts, explicit measurement protocols, or data exclusion criteria. This undermines assessment of whether the data support the headline numbers, as noted in the absence of these details even in the full text's standard CV/galvanostatic/EIS reporting.

    Authors: We agree that the original presentation would benefit from greater statistical detail. In the revised manuscript we have added error bars (standard deviation from n=3 independent electrodes) to all capacity, cycling, and rate data in the abstract, figures, and text. A new subsection in the Experimental Methods now specifies replicate counts, galvanostatic/CV/EIS protocols, and data exclusion criteria (outliers >3σ from mean). revision: yes

  2. Referee: [Mechanism discussion] Mechanism and performance attribution sections: The central claim that the di-block architecture enables an 'intermixed p/n-type storage mechanism' responsible for the high capacity, fast kinetics, and long cycling (including in ocean water) is not supported by a load-bearing control experiment. No comparison to physical mixtures of the individual bipyridinium and naphthalene diimide units or mono-block analogs is provided to isolate the di-block contribution, nor is there direct real-time evidence (beyond standard post-mortem SEM/FTIR and EIS) for simultaneous multi-ion exchange without side reactions.

    Authors: The referee is correct that the original submission did not contain direct comparisons to physical mixtures or mono-block analogs. We have therefore added new control data (electrochemical performance of mono-block bipyridinium and NDI oligomers plus a physical mixture) demonstrating inferior capacity retention and kinetics relative to the di-block DNVBr. In addition, we include in-situ Raman spectra acquired during cycling that show concurrent appearance of reduced bipyridinium and NDI signatures together with Cl- insertion, supporting simultaneous multi-ion exchange with no detectable side-reaction products. These additions are now in the revised Mechanism section. revision: yes

Circularity Check

0 steps flagged

No significant circularity

full rationale

This is a purely experimental materials science paper reporting measured electrochemical performance (capacities, cycling retention, CV/EIS data) of a synthesized oligomer in aqueous electrolytes. No equations, fitted parameters, predictions, or derivation chains exist that could reduce to inputs by construction. All claims rest on direct experimental outputs rather than any self-referential logic, self-citation load-bearing, or ansatz smuggling. The central performance numbers are therefore independent of any circular structure.

Axiom & Free-Parameter Ledger

0 free parameters · 0 axioms · 1 invented entities

This is an experimental report on a synthesized oligomer; the central claim rests on electrochemical performance metrics rather than mathematical axioms or derivations. No free parameters are fitted. The oligomer is a new chemical compound introduced via synthesis, not a postulated physical entity like a new particle.

invented entities (1)
  • DNVBr di-block oligomer no independent evidence
    purpose: Negative electrode material enabling intermixed p/n-type storage of Na+, Mg2+, and Cl-
    The oligomer is synthesized and tested in this work; the abstract provides no independent evidence outside the reported battery tests.

pith-pipeline@v0.9.0 · 5828 in / 1342 out tokens · 35400 ms · 2026-05-25T15:02:41.821210+00:00 · methodology

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Reference graph

Works this paper leans on

2 extracted references · 2 canonical work pages

  1. [1]

    E., Ciriello, R., Granafei, S., Guerrieri, A

    Carbone, M. E., Ciriello, R., Granafei, S., Guerrieri, A. & Salvi, A. M. EQCM and XPS investigations on the redox switching of conducting poly(o-aminophenol) films electrosynthesized onto Pt substrates. Electrochimica Acta 176, 926–940 (2015)

    work page 2015

  2. [2]

    , Liang, J., Huang, X., Hayakawa, T

    Nabae, Y. , Liang, J., Huang, X., Hayakawa, T. & Kakimoto, M. Sulfonic acid functionalized hyperbranched poly(ether sulfone) as a solid acid catalyst. Green Chem. 16, 3596–3602 (2014)

    work page 2014