All-organic self-separating three-dimensionally nanoarchitected electrochemical energy storage devices

2); (2) Robert Frederick Smith School of Chemical; (3) Department of Mechanical Engineering at Boston University; 4); (4) Division of Materials Science; 5; (5) Department of Design Tech at Cornell University; 6) ((1) Department of Materials Science; (6) Kavli Institute at Cornell for Nanoscale Science); Biomolecular Engineering at Cornell University

arxiv: 2604.26222 · v1 · submitted 2026-04-29 · ❄️ cond-mat.mtrl-sci · cond-mat.soft

All-organic self-separating three-dimensionally nanoarchitected electrochemical energy storage devices

William R. T. Tait (1 , 2) , Sriram Murali (1) , Chao-Hua Hsu (1) , Jantakan Nedsaengtip (2) , Christina Lee (1) , R. Paxton Thedford (2) , Vibha Kalra (2)

show 13 more authors

Joerg G. Werner (3 4) Ulrich B. Wiesner (1 5 6) ((1) Department of Materials Science Engineering at Cornell University (2) Robert Frederick Smith School of Chemical Biomolecular Engineering at Cornell University (3) Department of Mechanical Engineering at Boston University (4) Division of Materials Science Engineering at Boston University (5) Department of Design Tech at Cornell University (6) Kavli Institute at Cornell for Nanoscale Science)

This is my paper

Pith reviewed 2026-05-07 13:27 UTC · model grok-4.3

classification ❄️ cond-mat.mtrl-sci cond-mat.soft

keywords all-organic3D nanoarchitectedself-separatinglithium-ionsolid electrolyte interphaseelectropolymerizationenergy storageblock copolymer

0 comments

The pith

A monolithic carbon anode with co-continuous pores accepts an electropolymerized polymer cathode and then forms its own separator through electrochemical cycling to create an all-organic 3D nanoarchitected solid-state lithium-ion cell.

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

This paper establishes a fabrication route for three-dimensionally nanoarchitected electrochemical energy storage devices built entirely from organic materials. A block-copolymer-directed carbon structure supplies both the anode and a continuous pore network that is filled by electropolymerizing a single-phase conductive and redox-active polymer to serve as the cathode. Electrochemical cycling against external lithium then generates a solid electrolyte interphase inside the pores that functions as the separator while simultaneously lithiating both electrodes, after which the device operates as a solid-state full cell. The authors report a best discharge capacity of 267 mAh/g and show the same self-separating approach works with a second co-continuous carbon geometry. A reader would care because the method removes the need for a pre-placed separator and enables complex 3D electrode architectures from a single monolithic starting structure.

Core claim

The authors realize an all-organic 3D nanoarchitected EES device by directing the formation of a monolithic carbon anode with a co-continuous pore network using an ultra-large molar mass block copolymer, poly(styrene-block-2-dimethylaminoethyl methacrylate). Electropolymerization of poly((2,3-dihydrothieno[3,4-b][1,4]dioxin-2-yl)methyl 9,10-dioxo-9,10-dihydroanthracene-2-carboxylate) into the pore space creates the cathode. Subsequent cycling against lithium generates a solid electrolyte interphase that serves as the separator and lithiates the electrodes, enabling solid-state full-cell cycling with a maximum reported discharge capacity of 267 mAh/g. The design is further generalized to an a

What carries the argument

The co-continuous pore network within the block-copolymer-directed monolithic carbon anode, which permits uniform electropolymerization of the redox-active polymer cathode and subsequent in-situ formation of an SEI layer that acts as the separator.

If this is right

Establishes the first all-organic materials route to a 3D nanoarchitected EES device.
Introduces self-separating fabrication in which the separator is generated after the electrodes are already in contact.
Demonstrates solid-state operation of the full cell once the SEI has formed.
Shows the self-separating approach generalizes across different co-continuous carbon form factors.

Where Pith is reading between the lines

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

The method could allow fabrication of more intricate 3D electrode geometries that would be difficult to assemble if a separate separator sheet had to be inserted.
Electropolymerization into a pre-formed continuous pore network may be adaptable to other redox-active polymers or different pore sizes for tuning capacity or rate capability.
Because the entire device begins as a single monolithic structure, the approach could reduce the number of alignment steps required in manufacturing complex battery architectures.

Load-bearing premise

The electrochemically generated SEI layer will act as a reliable electronic separator between the two electrodes without producing short circuits or rapid capacity fade during full-cell cycling.

What would settle it

Cycling the assembled full cell and observing immediate short-circuit behavior or capacity falling to near zero within the first few cycles would show that the SEI does not function as a stable separator.

Figures

Figures reproduced from arXiv: 2604.26222 by 2), (2) Robert Frederick Smith School of Chemical, (3) Department of Mechanical Engineering at Boston University, 4), (4) Division of Materials Science, 5, (5) Department of Design Tech at Cornell University, 6) ((1) Department of Materials Science, (6) Kavli Institute at Cornell for Nanoscale Science), Biomolecular Engineering at Cornell University, Chao-Hua Hsu (1), Christina Lee (1), Engineering at Boston University, Engineering at Cornell University, Jantakan Nedsaengtip (2), Joerg G. Werner (3, R. Paxton Thedford (2), Sriram Murali (1), Ulrich B. Wiesner (1, Vibha Kalra (2), William R. T. Tait (1.

**Figure 2.** Figure 2: Schematic for the fabrication of self-separating all organic 3D battery and molecular structure of constituting organic structures/framework. From left to right, the device starts as a co-assembled hybrid from ultra-large molar mass (ULMM) BCP plus resols, which is then pyrolyzed under nitrogen into a large pore (~100 nm diameter) carbon. Counterintuitively, this carbon is then first used as a working elec… view at source ↗

read the original abstract

This work realizes a three-dimensionally (3D) nanoarchitected, all organic, "self-separating" lithium-ion electrochemical energy storage (EES) device that is cycled as a solid-state full cell. The device is enabled by a monolithic carbon anode with a co-continuous pore network, derived from the structure direction of resols by an ultra-large molar mass block copolymer (BCP), poly(styrene-block-2-dimethylaminoethyl methacrylate) (SA). Electropolymerization of a single-phase conductive and redox-active material, poly((2,3-dihydrothieno[3,4-b][1,4]dioxin-2-yl)methyl 9,10-dioxo-9,10-dihydroanthracene-2-carboxylate) (PAQEDOT), into the pore space provides the cathode of the cell. The device is electronically contacted to the relevant electrode network enabled by the co-continuous nature of each electrode. Electrochemical processing via cycling against external lithium in an electrolyte generates a solid electrolyte interphase (SEI) as a separator and lithiates the cell electrodes, after which the EES device is cycled in the solid state. While the full cell does not demonstrate high cyclability, the best full cell demonstrates a discharge capacity of 267 milliamp hours per gram (mAh/g). This work marks, to the best of knowledge of the authors, the first example of an all-organic materials derived 3D nanoarchitected EES device, as well as the first design of "self-separating" cell fabrication. Furthermore, generalization of the design to another co-continuous carbon form factor is demonstrated.

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.

Desk Editor's Note private letter to a colleague

This paper shows the first all-organic 3D nanoarchitected full cell using an in-situ SEI as separator and reports 267 mAh/g capacity, but the cycling is limited and the separator function lacks direct verification.

read the letter

The main point is a working all-organic 3D nanoarchitected lithium-ion cell made by templating a co-continuous carbon anode with a block copolymer, electropolymerizing an organic cathode into the pores, forming an SEI layer through cycling against lithium, and then running the device solid-state after electrolyte removal. They hit 267 mAh/g in the best cell and show the same route works on a second carbon structure. That self-separating step is the practical hook—no separate membrane to insert into a complex 3D geometry—and the monolithic networks give straightforward electronic contact to both electrodes. The fabrication sequence is cleanly executed and the generalization is a useful check that the method is not tied to one specific carbon form factor. The capacity number itself is a straightforward measurement with no fitted parameters or circularity issues. The soft spot is the performance data. The paper states outright that the full cell does not show high cyclability, yet there are no error bars, full cycle plots, leakage-current measurements, or post-cycling interface images to show whether the SEI is uniform, crack-free, and actually preventing shorts once the liquid electrolyte is gone. Without those checks the central claim that the electrochemically formed layer reliably serves as a separator rests on an assumption rather than direct evidence. The limited cycling could come from SEI instability, incomplete coverage, or micro-shorts, and the abstract does not resolve it. This is for groups working on 3D battery architectures or organic electrodes who want to see a new integration route. A reader looking for proof-of-concept fabrication details will find value; someone needing robust cycling or quantified separator metrics will want more. It deserves peer review because the novelty of the all-organic self-separating design is real and the basic device functions, even if the characterization needs tightening.

Referee Report

2 major / 2 minor

Summary. The manuscript reports the fabrication of an all-organic 3D nanoarchitected lithium-ion EES device using a monolithic carbon anode templated by an ultra-large molar mass block copolymer (SA) directing resols, with PAQEDOT electropolymerized into the co-continuous pore network as the cathode. An electrochemically generated SEI serves as the separator after electrolyte removal, enabling solid-state full-cell cycling with a peak discharge capacity of 267 mAh/g (though without high cyclability). The work claims to be the first all-organic materials-derived 3D nanoarchitected self-separating EES device and demonstrates generalization to another carbon form factor.

Significance. If the SEI-based self-separating mechanism is substantiated, the approach offers a novel route to simplify 3D battery assembly by eliminating traditional separators and enabling monolithic all-organic nanoarchitectures with co-continuous electrodes. The experimental demonstration of electropolymerization into BCP-templated pores and solid-state operation after SEI formation provides a concrete proof-of-concept for this fabrication strategy, which could impact design of high-surface-area organic EES devices.

major comments (2)

[Abstract and electrochemical characterization of full cell] Abstract and full-cell cycling results: The central claim that the electrochemically generated SEI reliably functions as a separator (preventing shorts after electrolyte removal) is load-bearing for the self-separating device concept, yet the manuscript explicitly states the full cell lacks high cyclability and provides no quantitative data on leakage currents, post-cycling EIS spectra, or cross-sectional imaging of the electrode-SEI interface to rule out micro-shorts, cracking, or incomplete coverage as the source of performance limitations.
[Results section on full cell assembly and testing] Results on device performance: The reported peak capacity of 267 mAh/g is presented without error bars, statistics from multiple devices, or direct baseline comparisons to non-self-separating controls or conventional separators, which weakens the ability to attribute the observed capacity specifically to successful SEI separator function rather than other factors.

minor comments (2)

[Abstract] The abstract could more clearly distinguish the achieved capacity from the noted lack of high cyclability to avoid potential misinterpretation of overall device performance.
[Methods and results] Notation for the block copolymer (SA) and polymer (PAQEDOT) is introduced without a dedicated nomenclature table or consistent abbreviation usage across figures and text.

Simulated Author's Rebuttal

2 responses · 2 unresolved

We thank the referee for their positive evaluation of the significance of our work and for the constructive feedback. We address the major comments point by point below, with clarifications on the scope of our claims and indications of where the manuscript will be revised.

read point-by-point responses

Referee: Abstract and full-cell cycling results: The central claim that the electrochemically generated SEI reliably functions as a separator (preventing shorts after electrolyte removal) is load-bearing for the self-separating device concept, yet the manuscript explicitly states the full cell lacks high cyclability and provides no quantitative data on leakage currents, post-cycling EIS spectra, or cross-sectional imaging of the electrode-SEI interface to rule out micro-shorts, cracking, or incomplete coverage as the source of performance limitations.

Authors: We concur that additional quantitative characterization of the SEI would strengthen the evidence for its role as a separator. The manuscript presents solid-state full-cell operation after electrolyte removal as a proof-of-concept, with the achieved discharge capacity indicating that immediate shorting is prevented. The limited cyclability is explicitly noted and may stem from electrode degradation or mechanical issues rather than micro-shorts. We do not possess post-cycling EIS spectra or cross-sectional imaging data of the SEI interface from the current experiments. We will revise the abstract and discussion sections to more precisely delineate the proof-of-concept scope and to discuss potential sources of performance limitations. revision: partial
Referee: Results on device performance: The reported peak capacity of 267 mAh/g is presented without error bars, statistics from multiple devices, or direct baseline comparisons to non-self-separating controls or conventional separators, which weakens the ability to attribute the observed capacity specifically to successful SEI separator function rather than other factors.

Authors: The value of 267 mAh/g represents the highest capacity from the best-performing device in this initial demonstration of the self-separating architecture. We will revise the results section to include any available replicate data or to note the single-device nature of the reported peak. Direct baseline comparisons to devices with conventional separators would help isolate the SEI contribution but fall outside the primary focus on the novel all-organic 3D fabrication route. We will add discussion clarifying the attribution of performance to the experimental design while acknowledging the absence of such controls. revision: partial

standing simulated objections not resolved

Quantitative leakage current measurements, post-cycling EIS spectra, and cross-sectional imaging of the electrode-SEI interface are not available from the experiments reported in the manuscript.
Statistical data across multiple devices and direct performance comparisons to non-self-separating or conventional-separator controls are not present in the current study.

Circularity Check

0 steps flagged

No significant circularity: purely experimental work with direct measurements

full rationale

The manuscript reports fabrication of a 3D nanoarchitected all-organic EES device via BCP-templated carbon anode, electropolymerization of PAQEDOT cathode, and electrochemical SEI formation followed by solid-state cycling. All key results (e.g., 267 mAh/g discharge capacity) are direct experimental outputs from galvanostatic cycling and materials characterization. No equations, fitted parameters, theoretical derivations, or predictions appear in the provided text. No load-bearing self-citations or ansatzes are invoked to justify any claimed result. The work is self-contained experimental demonstration; the reader's assessment of score 1.0 is consistent with absence of any circular structure.

Axiom & Free-Parameter Ledger

0 free parameters · 1 axioms · 0 invented entities

The work relies on established battery electrochemistry and polymer synthesis methods with no new free parameters, axioms beyond standard domain knowledge, or invented entities.

axioms (1)

domain assumption Standard lithium-ion battery electrochemistry including SEI formation and electrode lithiation.
Invoked implicitly when describing electrochemical processing and solid-state cycling.

pith-pipeline@v0.9.0 · 5765 in / 1211 out tokens · 48923 ms · 2026-05-07T13:27:16.625204+00:00 · methodology

discussion (0)

Reference graph

Works this paper leans on

6 extracted references · 6 canonical work pages

[1]

Department of Materials Science and Engineering, Cornell University, Ithaca, New York, United States

work page
[2]

Robert Frederick Smith School of Chemical and Biomolecular Engineering, Cornell University, Ithaca, New York, United States

work page
[3]

Department of Mechanical Engineering, Boston University, Boston, USA

work page
[4]

Division of Materials Science and Engineering, Boston University, Boston, USA

work page
[5]

Department of Design Tech, Cornell University; Ithaca, New York, United States

work page
[6]

Reaction and proton NMR characterization of (a, b) Br-EDOT and (c, d) AQEDOT

Kavli Institute at Cornell for Nanoscale Science, Cornell University, Ithaca, New York, United States * Corresponding author 38 Figure S1. Reaction and proton NMR characterization of (a, b) Br-EDOT and (c, d) AQEDOT. Figure S2. Schematic of custom glass electrochemical reactor set-up showing configuration for PEDOT current collector electropolymerization....

work page 2016

[1] [1]

Department of Materials Science and Engineering, Cornell University, Ithaca, New York, United States

work page

[2] [2]

Robert Frederick Smith School of Chemical and Biomolecular Engineering, Cornell University, Ithaca, New York, United States

work page

[3] [3]

Department of Mechanical Engineering, Boston University, Boston, USA

work page

[4] [4]

Division of Materials Science and Engineering, Boston University, Boston, USA

work page

[5] [5]

Department of Design Tech, Cornell University; Ithaca, New York, United States

work page

[6] [6]

Reaction and proton NMR characterization of (a, b) Br-EDOT and (c, d) AQEDOT

Kavli Institute at Cornell for Nanoscale Science, Cornell University, Ithaca, New York, United States * Corresponding author 38 Figure S1. Reaction and proton NMR characterization of (a, b) Br-EDOT and (c, d) AQEDOT. Figure S2. Schematic of custom glass electrochemical reactor set-up showing configuration for PEDOT current collector electropolymerization....

work page 2016