Maider Zarrabeitia

• PhD Material Science
• PhD at Karlsruhe Institute of Technology

Potassium-ion batteries (KIBs) have attracted significant attention in recent years as a result of the urgent necessity to develop sustainable, low-cost batteries based on non-critical raw materials that are competitive with market-available lithium-ion batteries. KIBs are excellent candidates, as they offer the possibility of providing high power...

In this work, the origin of Na ⁺ /vacancy orderings in P2-type Na x Ni y Mn 1− y O 2 is investigated. A general guideline to suppress Na ⁺ /vacancy orderings in P2-type Na x MO 2 cathode active materials is postulated.

Sodium-ion batteries are well positioned to become, in the near future, the energy storage system for stationary applications and light electromobility. However, two main drawbacks feed their underperformance, namely the irreversible sodium consumption during solid electrolyte interphase formation and the low sodiation degree of one of the most pro...

Improving electrochemical ion intercalation capacity and kinetics in layered host materials is a critical challenge to further develop lithium-ion batteries, as well as emerging cell chemistries based on ions beyond lithium. Modification of the nanoconfined interlayer space within host materials by synthetic pillaring approaches has emerged as a pr...

Sodium batteries are an attractive alternative for future energy storage as they can be produced with abundant and low-cost materials. Nonetheless, sodium-ion batteries (SIBs) are often composed of flammable and...

In the pursuit of more affordable battery technologies, potassium-ion batteries (KIBs) have emerged as a promising alternative to lithium-ion systems, owing to the abundance and wide distribution of potassium resources....

Aluminum–sulfur (Al–S) batteries have attracted extensive interest due to their high theoretical energy density, inherent safety, and low cost. However, severe polarization and poor cycling performance significantly limit the development of Al–S batteries. Herein, three-dimensional (3D) nitrogen-doped carbonaceous networks anchored with cobalt (Co@...

Na‐ion batteries based on abundant and sustainable materials might become one of the leading alternative technologies especially suitable for large‐scale stationary storage. Various (mixed)phosphate framework materials are attracting much interest mainly due to their high structural stability and diversity. In this study, we report on the successfu...

Potassium-ion batteries (PIBs) have attracted significant attention as a complement to lithium-ion and sodium-ion batteries. PIBs can theoretically provide higher specific energy and power density than sodium-ion batteries (SIBs) due to the lower standard electrode potential of K/K+ and faster K+ ion diffusion, maintaining the benefits of low-cost...

Low Coulombic efficiency and significant capacity decay resulting from an unstable solid electrolyte interphase (SEI) and dendritic growth pose challenges to the practical application of lithium‐metal batteries. In this study, a highly efficient protection layer induced by octaphenylsilsesquioxane (OPS) with LiFSI salt is investigated. The OPS exhi...

Special issue "Advanced Anode Materials for Alkali-Ion Batteries" for the open access journal Materials (from MDPI). Li-ion batteries (LIBs) are essential for powering many daily-used electronic devices, and keep gaining increasing interest because of their implementation in electric vehicles and their applicability in electric grid storage couple...

Na-ion batteries based on abundant and sustainable materials might become one of the leading alternative technologies especially suitable for large-scale stationary storage. Various (mixed)phosphate framework materials are attracting much interest mainly due to their high structural stability and diversity. In this study, we report on the successfu...

The commercialization of sodium-ion batteries (SIBs) is around the corner to support on electrification of various applications, especially focused on light electromobility and stationary applications. The anode of choice in SIBs is hard carbon (HC) following the success story of graphite anode in lithium-ion batteries. [1-4] One of the greatest ad...

Lithium-ion batteries (LIBs) have powered portable electronics and electric vehicles owing to their high energy density. In addition, the LIBs demand has significantly increased in the last years, raising concerns about the long-term availability and cost of the critical raw materials used in LIB production, e.g ., cobalt, lithium, natural graphite...

Li‐ion batteries (LIBs) are the powerhouse for the electronic devices in this modern mobile society, and enabler of the current communication revolution. Consumers demands advanced electronics and sustainable industries in general. To satisfy these demands, the new generation of rechargeable batteries need to provide much higher energy and power de...

Invited for this month's cover are the Electrochemistry for Batteries and Beyond Li: materials & interphases groups led by Prof. Stefano Passerini and Dr. Maider Zarrabeitia, respectively, at Helmholtz Institute Ulm (HIU). The cover picture shows a solvent‐free polymer electrolyte‐based sodium‐metal battery operating at room temperature for station...

NASICON-type Li1+xAlxTi2−x(PO4)3 (LATP) solid electrolytes have attracted great attention because of their high ionic conductivity, wide electrochemical stability window, pronounced chemical resistance, and low cost. However, the chemical instability of LATP against metallic lithium (Li0) poses a major challenge and hinders its application in solid...

Transitioning to solid‐state batteries using polymer electrolytes results in inherently safer devices and can facilitate the use of sodium metal anodes enabling higher energy densities. In this work, solvent‐free ternary polymer electrolytes based on cross‐linked polyethylene oxide (PEO), sodium bis(fluorosulfonyl) imide (NaFSI) or sodium bis(trifl...

The practical utilization of ether electrolytes has long been restricted due to the concern on its electrochemical oxidation stability. Recently, it has been demonstrated that ethers are compatible with a series of polyanionic cathodes for sodium batteries. However, the specific cathode-electrolyte interface is still poorly understood. In this work...

In this work we have shown our investigations on the use of fluorine-free cyano-based ionic liquid electrolyte composed of N-butyl-N-methylpyrrolidinium tricyanomethanide (Pyr14TCM), lithium dicyanamide (LiDCA) (1:9 salt:IL mole ratio) and 5 wt% vinylene carbonate (VC) have been performed in conjunction with silicon nanowire (Si NW) anodes. Their c...

Lithium-ion batteries (LIBs) are ubiquitous in all modern portable electronic devices such as mobile phones and laptops as well as for powering hybrid electric vehicles and other large-scale devices. Sodium-ion batteries (NIBs), which possess a similar cell configuration and working mechanism, have already been proven as ideal alternatives for larg...

The Cover Feature illustrates the magnetron sputtering process with variable ratio of Ar/N as process gas that leads to the formation of thin‐films of N‐containing LNMO high voltage cathodes. These results in improved electrochemical performance with respect to bare LNMO could be used to fabricate thin‐film high voltage Li‐ion batteries. More infor...

Nanocomposite materials consisting of metal oxide and carbon are of interest as electrode materials for both high rate intercalation-type and high capacity conversion-type charge storage processes. Facile synthesis processes like...

Delivering a commercial high‐voltage spinel LiNi0.5Mn1.5O4 (LNMO) cathode electrode for Li‐ion batteries would result in a significant step forward in terms of energy density. However, the structural ordering of the spinel and particle size have considerable effects on the cathode material's cyclability and rate capability, which are crucial challe...

The Cover Feature shows the sustainable cycle of hard carbon, the anode of choice for sodium‐ion batteries, produced from hazelnut shell bio‐waste, which is a highly abundant material in Europe. The developed hard carbon offers improved electrochemical properties, such as initial coulombic efficiency, specific capacity, long‐term stability, and rat...

Sodium‐ion batteries (SIBs) are postulated as sustainable energy storage devices for light electromobility and stationary applications. The anode of choice in SIBs is hard carbon (HC) due to its electrochemical performance. Among different HC precursors, bio‐waste resources have attracted significant attention due to their low‐cost, abundance, and...

Anode‐less” sodium metal batteries (SMBs) with high energy may become the next‐generation batteries due to the abundant resources. However, their cycling performance is still insufficient for practical uses. Herein, a metal organic frameworks (MOF)‐derived copper‐carbon (Cu@C) composite is developed as a sodiophilic layer to improve the Coulombic e...

The aqueous processing of lithium transition metal oxides into battery electrodes is attracting a lot of attention as it would allow for avoiding the use of harmful N-methyl-2-pyrrolidone (NMP) from the cell fabrication process and, thus, render it more sustainable. The addition of slurry additives, for instance phosphoric acid (PA), has been prove...

Regarding the cost and safety concerns arising together with the increasing demands on Lithium-ion batteries (LIBs), high energy density Ni-rich LiNi0.8Co0.1Mn0.1O2 (NMC811) materials are of substantial interest as cathode materials for the next-generation commercial LIBs. However, their low cycling stability hinders their use in large-scale applic...

The aqueous processing of lithium-containing electrode materials is challenged by the reactivity of such materials towards water, resulting in lithium leaching, slurry pH increase, and consequent corrosion of the aluminum current collector. The addition of (mild) acids to the aqueous electrode slurry has been reported as a viable method to suppress...

The poorly flammable room‐temperature ionic liquid‐based electrolyte composed of lithium bis(trifluoromethanesulfonyl)imide (LiTFSI) and N‐butyl‐N‐methylpyrrolidinium bis(fluorosulfonyl)imide (Pyr14FSI) with fluoroethylene carbonate (FEC) as an additive is investigated towards its compatibility with the LiNi0.88Co0.09Mn0.03O2 (NCM88) cathode and a...

Halide‐free, water‐in‐salt electrolytes (WiSEs) composed of potassium acetate (KAc) and zinc acetate (ZnAc2) are investigated as electrolytes in zinc‐ion hybrid supercapacitors (ZHSs). Molecular dynamics simulations demonstrate that water molecules are mostly non‐interacting with each other in the highly concentrated WiSEs, while “bulk‐like water”...

Rechargeable aqueous batteries are promising devices for large‐scale energy storage applications because of their low‐cost, inherent safety, and environmental friendliness. Among them, aqueous ammonium‐ion (NH4+) batteries (AAIB) are currently emerging owing to the fast diffusion kinetics of NH4+. Nevertheless, it is still a challenge to obtain sta...

Lithium metal is considered as one of the most promising anode candidates for high-energy batteries [1-3]. However, safety concerns induced by the formation of Li dendrites largely hinder the practical application of lithium-metal batteries [4]. It is anticipated that the use of non-flammable inorganic solid-state electrolytes can resolve these saf...

The ongoing electrification of the transportation sector is triggering a continuous search for batteries with higher energy density. One approach to achieve this goal is the transition to lithium-metal anodes. However, the practical implementation brings about severe safety issues such as the dendritic deposition and growth of metallic lithium and...

A novel fluorine-free ionic liquid electrolyte comprising lithium dicyanamide (LiDCA) and trimethyl(isobutyl)phosphonium tricyanomethanide (P111i4TCM) in a 1:9 molar ratio is studied as an electrolyte for lithium metal batteries. At room temperature, it demonstrates high ionic conductivity and viscosity of about 4.5 mS cm-1 and 64.9 mPa s, respecti...

Transition metal chalcogenides have been regarded as promising storage materials for sodium ions owing to their high theoretical capacity. Herein, copper‐based metal–organic frameworks (Cu‐BTC) are reported as precursors to fabrica copper chalcogenides‐carbon composites, namely Cu1.8S@C and Cu2‐xSe@C. The materials exhibit excellent electrochemical...

Solid‐state batteries (SSBs) are promising candidates to significantly exceed the energy densities of today's state‐of‐the‐art technology, lithium‐ion batteries (LIBs). To enable this advancement, optimizing the solid electrolyte (SE) is the key. β‐Li3PS4 (β‐LPS) is the most studied member of the Li2S‐P2S5 family, offering promising properties for...

To tackle the poor chemical/electrochemical stability of Li1+xAlxTi2‐x(PO4)3 (LATP) against Li and poor electrode|electrolyte interfacial contact, a thin poly[2,3‐bis(2,2,6,6‐tetramethylpiperidine‐N‐oxycarbonyl)norbornene] (PTNB) protection layer is applied with a small amount of ionic liquid electrolyte (ILE). This enables study of the impact of I...

The full commercialization of sodium‐ion batteries is still hindered by their lower electrochemical performance and higher cost ($ W‐1 h‐1) with respect to lithium‐ion batteries. Understanding the electrode‐electrolyte interphase formation in both electrodes is crucial to increase the cell performance and, ultimately, reduce the cost. Herein, a ste...

Single‐ion conducting polymer electrolytes are considered particularly attractive for realizing high‐performance solid‐state lithium‐metal batteries. Herein, a polysiloxane‐based single‐ion conductor (PSiO) is investigated. The synthesis is performed via a simple thiol‐ene reaction, yielding flexible and self‐standing polymer electrolyte membranes...

P2-Na2/3[Fe1/2Mn1/2]O2 layered oxide is a promising high energy density cathode material for sodium-ion batteries. However, one of its drawbacks is the poor long-term stability in the operating voltage window of 1.5–4.25 V vs Na+/Na that prevents its commercialization. In this work, additional light is shed on the origin of capacity fading, which h...

Rechargeable Li-ion battery technology has progressed due to the development of a suitable combination of electroactive materials, binders, electrolytes, additives, and electrochemical cycling protocols that resulted in the formation of a stable electrode-electrolyte interphase. It is expected that Na-ion technology will attain a position comparabl...

Organic cations are essential components of locally concentrated ionic liquid electrolytes (LCILEs), but receive little attention. Herein, we demonstrate their significant influence on the electrochemical performance of lithium metal batteries via a comparison study of two LCILEs employing either 1-butyl-1-methylpyrrolidinium cation (Pyr14⁺) or 1-e...

High‐energy Ni‐rich lithium transition metal oxides such as Li[Ni0.8Co0.1Mn0.1]O2 (NCM811) are appealing positive electrode materials for next‐generation lithium batteries. However, the high sensitivity toward moist air during storage and the high reactivity with common organic electrolytes, especially at elevated temperatures, are hindering their...

NASICON‐type Li1+xAlxTi2−x(PO4)3 (LATP) solid electrolytes have developed as a promising candidate for solid‐state lithium batteries. However, the brittle and stiff LATP suffers from poor physical contact with electrodes and chemical/electrochemical instability at electrode|electrolyte interfaces. Herein, a thin and flexible hybrid electrolyte comp...

FSI⁻‐based ionic liquids (ILs) are promising electrolyte candidates for long‐life and safe lithium metal batteries (LMBs). However, their practical application is hindered by sluggish Li⁺ transport at room temperature. Herein, it is shown that additions of bis(2,2,2‐trifluoroethyl) ether (BTFE) to LiFSI‐Pyr14FSI ILs can effectively mitigate this sh...

Hard carbon (HC) is the negative electrode (anode) material of choice for sodium‐ion batteries (SIBs). Despite its advantages in terms of cost and sustainability, a comprehensive understanding of its microstructure is not complete yet, thus hindering a rational design of high‐performance HC electrodes. In this study, rather than investigating how t...

The abundance of the available sodium sources has led to rapid progress in sodium-ion batteries (SIBs), making them potential candidates for immediate replacement of lithium-ion batteries (LIBs). However, commercialization of SIBs has been hampered by their fading efficiency due to the sodium consumed in the formation of solid-electrolyte interphas...

Sodium-ion batteries (SIBs) have been postulated as a potential solution for large-scale stationary application and light electromobility. Among positive electrode materials for SIBs, Na4Co3(PO4)2P2O7 attracted significant attention due to its high voltage and good specific capacity even at very high current densities. However, details of the forme...

Cyano‐based ionic liquids (ILs) are prime candidates for the manufacturing of cheaper and safer batteries due to their inherently low‐volatility and absence of expensive fluorinated species. In this work, N‐methyl‐N‐butylpyrrolidinium (Pyr14)‐based ILs featuring two different cyano‐based anions, i.e., dicyanamide (DCA) and tricyanomethanide (TCM),...

V2O5, one of the earliest intercalation-type cathode materials investigated as a Li+ host, is characterized by an extremely high theoretical capacity (441 mAh g–1). However, the fast capacity fading upon cycling in conventional carbonate-based electrolytes is an unresolved issue. Herein, we show that using a LiTFSI/tetraglyme (1:1 in mole ratio) el...

Sodium-ion batteries (SIBs) are amongst the most attractive alternatives for stationary applications and light electromobility due to potentially substantial cost reductions resulting from the availability, wide distribution, and easily accessible nature its constituents. However, commercialization is hindered-especially by lack of high-performance...

Vanadium oxides have been recognized to be among the most promising positive electrode materials for aqueous zinc metal batteries (AZMBs). However, their underlying intercalation mechanisms are still vigorously debated. To shed light on the intercalation mechanisms, high-performance δ-V2O5 is investigated as a model compound. Its structural and ele...

The extensive investigation via classical Molecular Dynamics (MD) simulations of the halide-free “water-in-salt” electrolyte (WiSE) consisting of sodium acetate (8 m) and potassium acetate (32 m), unveils the interactions between cations, anions and water molecules. The WiSE's application as electrolyte in symmetric aqueous sodium-ion batteries, fe...

Aqueous rechargeable alkali-ion batteries have attracted considerable interest in recent years due to reduced cost, lower environmental impact and, most importantly, and improved safety. ¹ Unfortunately, the narrow electrochemical stability window of water (1.23 V) limits the maximum output voltage of aqueous batteries, thus leading to intrinsicall...

The use of cobalt-free LiNi0.5Mn1.5O4 (LNMO) would provide a great leap forward towards the realization of sustainable lithium-ion batteries. However, the high operating voltage remains to be a great challenge for the cathode/electrolyte stability. Herein, we report a rational material design to address these challenges by carefully tuning the synt...

Potassium acetate (KAc)-based “Water-in-salt” electrolytes (WiSEs) are herein studied by Raman and classical Molecular Dynamics (MD), evidencing the notably suppressed water activity of these WiSEs since water can be effectively coordinated by both the acetate anion and the potassium cation. The overall molecular arrangement is found to approach th...

Herein we report a series of lithium ion capacitors (LICs) with extraordinary energy-to-power ratios based on olive pit recycled carbons and supported on graphene as a conducting matrix. LICs typically present limited energy densities at high power densities due to the sluggish kinetics of the battery-type electrode. To circumvent this limitation,...

The electrochemical properties of P2- Na2/3Mn0.8Fe0.1Ti0.1O2 layered oxide, which is a promising cathode material for rechargeable Na-ion batteries (NIBs), are evaluated with with an optimized in-house ionic liquid (IL)-based electrolyte and compared with its performance when using carbonate-based electrolyte. The IL-based system reveals better ele...

Na4Co3(PO4)2P2O7, a high voltage positive Na-ion electrode material, is thoroughly analyzed by coupling operando X-ray diffraction (XRD) and electrochemical impedance spectroscopy (EIS) measurements. Na4Co3(PO4)2P2O7 follows a complex structural evolution upon electrochemical cycling via four consecutive biphasic reactions followed by a single-phas...

The many advantages of Na-ion batteries (NIBs) in terms of availability and cost of raw materials if compared with Li-ion batteries (LIBs) are hindered by the stability of the Na-based electrodes. The most promising NIB positive electrodes are Co- and Ni-free sodium manganese rich layered oxides with general formula NaxMn1-yTMy-zT’MzO2 (y < 0.33, T...

Tavorite NaTiOPO4 (NaTP) is here explored as a possible Solid Electrolyte Interphase (SEI) - free anode material for Na-ion batteries (NIBs). The operation voltage is found around 1.4 V vs. Na+/Na with a very low polarization (around 0.02 V) and an efficiency of ~95% after 100 cycles. Operando X-ray diffraction measurements have unveiled that inser...

The electrochemical properties of Na4Fe3(PO4)2P2O7 in aqueous and organic electrolyte are compared under similar conditions. Na4Fe3(PO4)2P2O7 is able to deliver almost the same capacity in both types of electrolytes despite the smaller electrochemical window entailed by the aqueous one. As shown by electrochemical impedance spectroscopy (EIS), this...

Na2Ti3O7 is a promising negative electrode for rechargeable Na-ion batteries; however, its good properties in terms of insertion voltage and specific capacity are hampered by the poor capacity retention reported in the past. The interfacial and ionic/electronic properties are key factors to understanding the electrochemical performance of Na2Ti3O7....

This communication reports the first experimental evidence of an interesting change of transport properties, and particularly of electron conductivity, during the Na⁺ insertion/extraction process in Na2Ti3O7 negative electrodes. Probed by electrochemical impedance spectroscopy, for 0.0 ≤ x < 1.4 in Na2+xTi3O7 the material exhibits insulator behavio...

Na 2 Ti 3 O 7 is a promising negative electrode for Na-ion batteries (NIBs) with a very low insertion voltage (0.3 V vs. Na ⁺ /Na) and high specific capacity (178 mAh/g) [1, 2]. However, Na 2 Ti 3 O 7 shows poor capacity retention when synthesized from Na 2 CO 3 as sodium precursor, reaching only 50-70% of capacity retention after 10 cycles [3, 4,...

Na2Ti3O7 is a promising insertion anode material for Na-ion batteries owing to its low reaction voltage (0.3 V vs. Na+/Na) and high specific capacity (178 mAh/g). However, such promising attributes are shaded by the poor capacity retention that has so far been obtained for this material. Here the impact of solid state synthesis parameters on the el...

Sodium ion batteries (SIBs) are becoming an attractive alternative for stationary applications because of their low cost: sodium is more abundant and easier to obtain than lithium and cheaper current collectors made of aluminium instead of copper can be used. While for cathode materials many lithium analogues can be successfully used in SIB [1], th...

Na2Ti3O7 is considered a promising negative electrode for Na-ion batteries; however, poor capacity retention has been reported and the stability of the solid-electrolyte interphase (SEI) could be one of the main actors of this underperformance. The composition and evolution of the SEI in Na2Ti3O7 electrodes is hereby studied by means of X-ray photo...

H2Ti3O7 was prepared as a single phase by ionic exchange from Na2Ti3O7. The complete ionic exchange was confirmed by 1H and 23Na solid state NMR. The atomic positions of H2Ti3O7 were obtained from the Rietveld refinement of powder X-ray diffraction and neutron diffraction experimental data, the latter collected at two different wavelengths to preci...