On‐chip micro‐supercapacitors (MSCs), as promising power candidates for microdevices, typically exhibit high power density, large charge/discharge rates, and long cycling lifetimes. However, as for most reported MSCs, the unsatisfactory areal energy density (<10 µWh cm−2) still hinders their practical applications. Herein, a new‐type Zn‐ion hybrid MSC with ultrahigh areal energy density and long‐term durability is demonstrated. Benefiting from fast ion adsorption/desorption on the capacitor‐type activated‐carbon cathode and reversible Zn stripping/plating on the battery‐type electrodeposited Zn‐nanosheet anode, the fabricated Zn‐ion hybrid MSCs exhibit remarkable areal capacitance of 1297 mF cm−2 at 0.16 mA cm−2 (259.4 F g−1 at a current density of 0.05 A g−1), landmark areal energy density (115.4 µWh cm−2 at 0.16 mW cm−2), and a superb cycling stability without noticeable decay after 10 000 cycles. This work will inspire the fabrication and development of new high‐performance microenergy devices based on novel device design.

No description available.

Philosophiae Doctor - PhD (Chemistry) / Lithium ion capacitors are new and promising class of energy storage devices formed from a combination of lithium-ion battery electrode materials with those of supercapacitors. They exhibit better electrochemical properties in terms of energy and power densities than the above mentioned storage systems. In this work, lithium manganese oxide spinel (LiMn2O4; LMO) and lithium manganese phosphate (LiMnPO4; LMP) as well as their respective nickel-doped graphenised derivatives (G-LMNO and G-LMNP) were synthesized and each cathode material used to fabricate lithium ion capacitors in an electrochemical assembly that utilised activated carbon (AC) as the negative electrode and lithium sulphate electrolyte in a two-electrode system. The synthetic protocol for the preparation of the materials followed a simple solvothermal route with subsequent calcination at 500 - 800 ?C. The morphological, structural and electrochemical properties of the as prepared materials were thoroughly investigated through various characterisation techniques involving High resolution scanning electron microscopy (HRSEM), High resolution transmission electron microscopy (HRTEM), Fourier transform infrared spectroscopy (FTIR), Raman spectroscopy, X-ray diffraction (XRD), Small-angle X-ray scattering (SAXS), Electrochemical impedance spectroscopy (EIS), Cyclic voltammetry (CV) and Galvanostatic charge/discharge.

Energy Harvesting, also known as power harvesting or ambient power, is the process of obtaining small amounts of power from secondary sources, such as vibrations, light, temperature variations and even radio-frequency emissions. These systems have been uncommon in personal and wearable electronics in the past, however they are slowly gaining traction. With the increasing sophistication of prosthetic limbs and implants, devices that in some cases require a consistent and reliable power source, the potential field of application for energy harvesting grows wider. This thesis project evaluates whether energy harvesting methods could be implemented in future prosthetic limb designs without significantly affecting weight, user comfort, complexity of design etc., and whether the gains of such an implementation would be worth the effort and cost put into it. For reference the project used the RHEO KNEE® by Össur Hf., a microcontroller controlled prosthetic knee, as a device that such a system could be integrated with. Energy harvesting is still an emerging field and is a long time away from being a viable primary power source for most electronic devices. However, it still might have potential as a supplementary source for extending charge cycles or making smaller (and therefore more lightweight) power cells viable. This master’s thesis project was broad in scope and included 3D-design; mechanical, electrical and embedded software design; and setting up a miniature kinetic power generator as well as a photovoltaic harvesting system. No amputees were available for testing the designs so the system was tested with a 3D-printed model that was moved by hand to simulate the generation process. Due to some incorrect inital assumptions, the final electronic design was not optimal for this kind of system. However, a kinetic generator that harvested power from a modeled heel striking the ground 50 times a minute produced about 23mW of power. 53cm2 of photovoltaic panels produced 42μW of power in an ambient light setting. For comparison, a low-power microcontroller needed about 119μW of power on average to do some simple processing and send Bluetooth transmissions once every two seconds. / Energiinsamling (e. Energy Harvesting), är processen för att erhålla små mängder kraft från sekundära källor, såsom vibrationer, ljus, temperaturvariationer och utstrålning i radiofrekvens. Dessa system har varit ovanliga i hemelektronik och bärbar teknik, men de vinner sakta dragkraft. Med den ökande förfining av proteser och implantat, som i vissa fall kräver en jämn och pålitlig strömkälla, växer det potentiella användningsområdet för energiinsamling. Detta examensarbete utvärderar huruvida energiinsamlingsmetoder skulle kunna implementeras i framtida proteskonstruktioner utan att nämnvärt påverka vikt, användarkomfort, komplexitet i design etc., och om vinsterna med en sådan implementering skulle vara värd ansträngningen och kostnaden. Som exempel använde detta projekt en datoriserad knäprotes av Össur HF, RHEO KNEE®, som exempel på ett system som energiinsamling skulle kunna integreras med. Energiinsamling är fortfarande ett växande forskningsområde och är långt ifrån att en strömkälla för det mesta elektronik.. Det kan ändå ha potential som en kompletterande strömkälla som kan förlänga laddningscykler eller göra mindre (och därför lättare) batterier möjliga. Detta examensarbete var brett i omfattning och inkluderade 3D-design; mekanisk-, elektrisk- och mjukvara-design; och inrättning av en kinetisk kraftgenerator i miniatyr samt ett ljusdrivet energiinsamlingssystem. Inga amputerade var tillgängliga för att testa designen, därför så testades systemet med en 3D-printad modell som rördes för hand för att simulera strömförsörjelseprocessen. På grund av några felaktiga initiala antaganden var den slutliga elektroniska designen inte optimal för denna typ av system. Ändå lyckades en kinetisk generator som använde energiinsamlingsprinciper producera cirka 23mW ström genom en simulerad häl som träffade marken cirka 50 gånger i minuten. 53cm2 solcellspaneler producerade 42μW energi i en ljussatt miljö. Som jämförelse behövde en strömsnål styrkrets i genomsnitt cirka 119μW effekt för att genomföra enkla programprocesser och skicka Bluetooth-överföringar en gång varannan sekund. / Hliðarorkuöflun (e. energy harvesting), sem einnig bætti kalla umhverfisöflun, er ferlið við að fá lítið magn af orku frá óbeinum aflgjafa, svo sem frá hristingi, ljósi, hitabreytingum og jafnvel útvarpsbylgjum. Þessi kerfi hafa verið sjaldgæf í raftækjum hingað til, þó þau eru hægt og rólega að fá hlutdeild. Með nýrri og fágaðri gervilimum og ígræðslum, tæki sem í sumum tilvikum þurfa samfellda og áreiðanlega orkjugjafa, víkkar mögulegt notkunarsvið hliðarorkuöflunar. Þetta lokaverkefni metur hvort aðferðir við hliðarorkuöflun gætu verið notaðar í hönnun gervilima framtíðarinnar án þess að hafa neikvæð áhrif á þyngd, þægilegheit, flóknun hönnunar o.þ.h., og hvort hagur sé í samræmi við framlag og kostnað. Þetta verkefni notar RHEO KNEE® frá Össuri Hf. sem viðmið, sem er gervihné stjórnað af örtölvu. Viðmiðinu er ætlað að sýna notagildi kerfisins. Hliðarorkuöflun er ennþá svið í þróun og er nokkuð í að það geti orðið frumorkugjafi fyrir flest raftæki. Hins vegar þá gæti það enn átt möguleika á að vera aukaorkugjafi til að auka tímalengd hverrar hleðslu eða gera minni og léttari rafhlöður raunhæfari. Þetta meistaraverkefni var viðamikið að því leiti að það fól í sér þrívíddarhönnun; vél-, raf- og hugbúnaðarhönnun; og uppsetningu á hreyfirafal ásamt ljósorkuöflunarkerfi. Engir einstaklingar sem misst hafa fót voru til staðar til að prófa hannanir þessa verkefnis. Þ.a.l. voru þær prófaðar með þrívíddarprentuðum líkönum sem hreyfð voru með handafli til að líkja eftir orkuframleiðsluferlinu. Vegna rangrar upprunalegrar forsendu þá var endanleg rafhönnunin ekki ákjósanleg fyrir slíkt kerfi. Hreyfirafall tengdur við gervihæl sem sló jörðu 50 sinnum á mínútu framleiddi þó 23mW af orku. 53cm2 af ljósorkueiningum framleiddu 42μW af afli í meðal herbergisbirtu. Til samanburðar þá eyðir skilvirk örtölva u.þ.b. 119μW af afli í einfaldri tölvuvinnslu ásamt því að senda Bluetooth sendingu á tveggja sekúnda fresti.

Die vorliegende Arbeit konzentriert sich auf die Synthese von neuartigen hohlen MoSx-Nanomaterialien mit kontrollierbarer Größe und Form durch die kolloidale Template Methode. Ihre möglichen Anwendungen in wässrigen Energiespeichersystemen, einschließlich Superkondensatoren und Li-Ionen-Batterien (LIBs), wurden untersucht. Im ersten Teil wurde eine neue Nanostruktur aus hohlen Kohlenstoff-MoS2-Kohlenstoff-nanoplättchen erfolgreich durch eine L-Cystein unterstützte hydrothermale Methode unter Verwendung von Gibbsit als Templat und Polydopamin (PDA) als Kohlenstoffvorläufer synthetisiert. Nach dem Kalzinieren und Ätzen des Gibbsit Templates wurden gleichförmige Hohlplättchen erhalten, die aus einer sandwichartigen Anordnung von teilweise graphitischem Kohlenstoff und zweidimensional geschichteten MoS2 Flocken bestehen. Die Plättchen haben eine ausgezeichnete Dispergierbarkeit und Stabilität in Wasser sowie eine gute elektrische Leitfähigkeit aufgrund des durch die Kalzinierung von Polydopaminbeschichtungen erzeugten Kohlenstoffs gezeigt. Das Material wird dann in einem symmetrischen Superkondensator mit 1 M Li2SO4 als Elektrolyt aufgebracht, der eine spezifische Kapazität von 248 F/g (0.12 F/cm2) bei einer konstanten Stromdichte von 0.1 A/g und eine ausgezeichnete elektrochemische Stabilität über 3000 Zyklen aufweist, was darauf hindeutet, dass hohle Kohlenstoff-MoS2-Kohlenstoffnanoplättchen vielversprechende Materialien als Kandidaten für Superkondensatoren sind. Im zweiten Teil wurde 21 molare LiTFSI, das sogenannte "Wasser-in-Salz" (WIS) Elektrolyt, in Superkondensatoren mit hohlen Kohlenstoffnanoplättchen als Elektrodenmaterial untersucht. Im Vergleich zu dem im ersten Teil verwendeten 1 molaren Li2SO4-Elektrolyten wurden bei dem vorliegenden WIS Elektrolyt signifikante Verbesserungen in einem breiteren und stabilen Potentialfenster festgestellt, das durch die geringere Leitfähigkeit mit dem Gegenstück leicht beeinflusst wird. Die elektrochemische Impedanzspektroskopie (EIS) wurde ausgiebig eingesetzt, um einen Einblick in die Reaktionsmechanismen der WIS-Superkondensatoren zu erhalten. Zusätzlich wurde auch der Einfluss der Temperatur auf die elektrochemische Leistung im Temperaturbereich zwischen 15 und 55 °C untersucht, was eine hervorragende spezifische Kapazität von 128 F/g bei dem optimierten Zustand von 55 °C ergab. Die EIS-Messungen deckten die Abnahme der angepassten Widerstände mit der Temperaturerhöhung und umgekehrt auf und beleuchteten direkt die Beziehung zwischen elektrochemischer Leistung und Arbeitstemperatur von Superkondensatoren für zuverlässige praktische Anwendungen. Im dritten Teil wurde MoS3, ein amorphes, kettenförmig strukturiertes Übergangsmetall Trichalcogenid, als vielversprechende Anode in "Wasser-in-Salz" Li-Ionen-Batterien (WIS-LIBs) nachgewiesen. Die in diesem Teil verwendeten hohlen MoS3-Nanosphären wurden mittels einer skalierbaren Säurefällungsmethode bei Raumtemperatur synthetisiert, wobei sphärische Polyelektrolytbürsten (SPB) als Schablonen verwendet wurden. Beim Einsatz in WIS-LIBs mit LiMn2O4 als Kathodenmaterial erreicht das präparierte MoS3 eine hohe spezifische Kapazität von 127 mAh/g bei einer Stromdichte von 0.1 A/g und eine gute Stabilität über 1000 Zyklen sowohl in Knopf- als auch in Pouch-Zellen. Der Arbeitsmechanismus von MoS3 in WIS-LIBs wurde auch durch Ex-situ-Röntgenbeugungsmessungen (XRD) untersucht. Während des Betriebs wird MoS3 während der anfänglichen Li-Ionen-Aufnahme irreversibel in Li2MoO4 umgewandelt und dann allmählich in eine stabilere und reversible LixMoOy-Phase (2≤y≤4)) entlang der Zyklen umgewandelt. Amorphes Li-defizientes Lix-mMoOy/MoOz wird bei der Delithiierung gebildet. Die Ergebnisse der vorliegenden Studie zeigen einfache Ansätze zur Synthese hohler MoSx-Nanomaterialien mit kontrollierbarer Morphologie unter Verwendung einer Template-basierten Methode, die auf die vielversprechende Leistung von MoSx für wässrige Energiespeicheranwendungen zurückzuführen sind. Die elektrochemischen Untersuchungen von hohlen MoSx-Nanomaterialien in wässrigen Elektrolyten geben Einblick in die Reaktionsmechanismen von wässrigen Energiespeichersystemen und treiben die Entwicklung von Metallsulfiden für wässrige Energiespeicheranwendungen voran. / The present thesis focuses on the synthesis of novel hollow MoSx nanomaterials with controllable size and shape through the colloidal template method. Their possible applications in aqueous energy storage systems, including supercapacitors and Li-ion batteries (LIBs), have been studied. In the first part, hollow carbon-MoS2-carbon nanoplates have been successfully synthesized through an L-cysteine-assisted hydrothermal method by using gibbsite as the template and polydopamine (PDA) as the carbon precursor. After calcination and etching of the gibbsite template, uniform hollow platelets, which are made of a sandwich-like assembly of partial graphitic carbon and two-dimensional layered MoS2 flakes, have been obtained. The platelets have shown excellent dispersibility and stability in water, and good electrical conductivity due to carbon coating generated by the calcination of polydopamine. The material is then applied in a symmetric supercapacitor using 1 M Li2SO4 as the electrolyte, which exhibits a specific capacitance of 248 F/g (0.12 F/cm2) at a constant current density of 0.1 A/g and an excellent electrochemical stability over 3000 cycles, suggesting that hollow carbon-MoS2-carbon nanoplates are promising candidate materials for supercapacitors. In the second part, 21 m LiTFSI, so-called “water-in-salt” (WIS) electrolyte, has been studied in supercapacitors with hollow carbon nanoplates as electrode materials. In comparison with 1 M Li2SO4 electrolyte used in the first part, significant improvements on a broader and stable potential window have been revealed in the present WISE, which is slightly influenced by the lower conductivity with the counterpart. The electrochemical impedance spectroscopy (EIS) has been extensively employed to provide an insight look on the formation of solid electrolyte interphase in the WIS-supercapacitors. Additionally, the effect of temperature on the electrochemical performance has also been investigated in the temperature range between 15 and 55 °C, yielding eminent specific capacitance of 128 F/g at the optimized condition of 55 °C. The EIS measurements disclosed the decrease of fitted resistances with the increase of temperature and vise versa, directly illuminating the relationship between electrochemical output and working temperature of supercapacitors for reliable practical applications. In the third part, MoS3, an amorphous chain-like structured transitional metal trichalcogenide, has been demonstrated as a promising anode in the “water-in-salt” Li-ion batteries (WIS-LIBs). Hollow MoS3 nanospheres used in this part have been synthesized via a scalable room-temperature acid precipitation method using spherical polyelectrolyte brushes (SPB) as the template. When applied in WIS-LIBs with LiMn2O4 as the cathode material, the prepared MoS3 achieves a high specific capacity of 127 mAh/g at the current density of 0.1 A/g and good stability over 1000 cycles in both coin cells and pouch cells. The working mechanism of MoS3 in WIS-LIBs has also been studied by ex-situ X-ray diffraction (XRD) measurements. During operation, MoS3 undergoes irreversible conversion to Li2MoO4 during the initial Li ion uptake, and is then gradually converted to a more stable and reversible LixMoOy (2≤y≤4)) phase along cycling. Amorphous Li-deficient Lix-mMoOy/MoOz is formed upon delithiation. The results in the present thesis demonstrate facile approaches for synthesizing hollow MoSx nanomaterials with controllable morphologies using a template-based method, which attribute to the promising performance of MoSx for aqueous energy storage applications. The electrochemical studies of hollow MoSx nanomaterials in aqueous electrolytes provide insight into the reaction mechanisms of aqueous energy storage systems and push forward the development of metal sulfides for aqueous energy storage applications.

Resolving the mismatch between the practical potential window (PPW) and the available capacitive potential window of supercapacitor electrodes provides a feasible way to expand the operating voltage of supercapacitors, which further boosts energy density. Here, our research unveils a unique approach to manually control the PPW of the corresponding carbon-based supercapacitors (CSCs) by rational functionalization with amino groups. The extra pair of electrons from amino N atoms naturally adsorbs cations in the electrolyte, which rationalizes the surface charge of the carbon electrode and adjusts the PPW. A remarkable voltage expansion is achieved for CSCs, from 1.4 V to its maximum limit, 1.8 V, correspondently resulting in an approximately 1-fold increase in the energy density. Importantly, such a simple strategy endows our CSCs with an outstanding maximum energy density of 7.7 mWh cm⁻³, which is not only among the best values reported for thin-film CSCs but also comparable to those reported for Li thin-film batteries. These encouraging results are believed to bring fundamental insights into the nature of potential control in energy storage devices.

Les supercapacités électrochimiques sont des dispositifs de stockage d’énergie à haute puissance, permettant d’emmagasiner et de relarguer l’énergie très rapidement. Parce qu’ils ne peuvent stocker de grandes quantités d’énergie, ces dispositifs sont souvent utilisés en tandem avec des batteries qui, elles, ont de grandes densités d’énergie. Le stockage d’énergie dans les supercapacités se fait principalement par le déplacement des ions dans la double couche électrique de carbones activés (élaboré par un traitement thermique en base concentrée pour augmenter la taille et la quantité des pores) à haute surface spécifique. La présence de réactions faradiques lors du stockage permettrait d’augmenter l’énergie spécifique des supercapacités et d’en améliorer l’utilisation. L’approche préconisée dans le groupe Rochefort pour arriver à ce but est d’ajouter une espèce redox soluble dans l’électrolyte. Les liquides ioniques redox (donc modifiés avec un centre électroactif) sont particulièrement prometteurs par leur grande solubilité dans les électrolytes à base de solvants organiques. Il y a toutefois bien peu de connaissances sur leur fonctionnement et leurs interactions avec les électrodes de carbone activé. Dans le cadre de ce mémoire, nous avons étudié les interactions entre un liquide ionique redox modifié avec le groupement ferrocène [EMIm][FcNTf] (1-Ethyl-3-methylimidazolium Ferrocénylsulfonyl(trifluorométhylsulfonyl) imide) et deux matériaux en carbone poreux. L’utilisation de deux carbones commerciaux YP-80F et YP-50F, qui ont une des formes de pores semblable, mais des distributions des pores différentes, a permis de mieux comprendre l’effet de la taille des pores sur le stockage. Le carbone avec la plus grande proportion de pores de grande taille allant jusqu’à 3 nm, le YP-80F, a révélé une forte augmentation de l’énergie spécifique de l’ordre de 30 % à 40 % par rapport à celui avec des pores plus restreints (32,9 Wh/kg pour YP-80F contre 19,7 Wh/kg pour YP-50F). Pour déterminer si l’augmentation de l’énergie spécifique est à l’origine d’une meilleure accessibilité des ions redox volumineux aux pores du carbone, nous avons utilisé la spectroscopie de résonance magnétique nucléaire à l’état solide (RMN en 19F). Les études RMN ont montré que le carbone YP-80F, lors de sa charge, contient une plus grande proportion d’ions dans les pores que le YP-50F qui présente des pores de plus petite taille. Ces résultats permettront de développer des espèces électroactives mieux adaptées aux carbones avec lesquels elles sont utilisées et d’améliorer le stockage d’énergie dans les supercapacités électrochimiques. / Electrochemical supercapacitors are high-power energy storage devices that can store and release energy very quickly. Because they cannot store large quantities of energy, these devices are often used in tandem with batteries, which have high energy densities. Energy storage in supercapacitors is mainly achieved by moving ions in the electric double layer of activated carbons with high specific surface area. The addition of faradic reactions during storage would increase the specific energy of supercapacitors and improve their utilization. The approach followed by the Rochefort group to achieve this goal is to add a soluble redox species to the electrolyte of the supercapacitor. Redox ionic liquids (i.e. modified with an electroactive center) are particularly promising because of their high solubility in electrolytes. However, very little is known about how they work and interact with activated carbon electrodes. In this work, we studied the interactions between a redox ionic liquid modified with the ferrocene moiety and two porous carbon materials. Using two commercial carbons YP-80F and YP-50F, which have similar porosity but different pore distributions, we were able to gain a better understanding of the effect of pore size on storage. The carbon with the highest proportion of large pores, YP-80F, showed a strong increase in specific energy of the order of 30% to 40% over that with smaller pores (32,9 Wh/kg for YP-80F vs. 19,7 Wh/kg for YP-50F). Solid-state nuclear magnetic resonance (NMR) spectroscopy was used to determine whether the increase in specific energy was due to greater accessibility of bulky redox ions to the carbon pores. NMR studies have shown that YP-80F carbon, when charged, contains a higher proportion of ions in the porosity than YP-50F, which has a more restricted porosity. These results will enable us to develop electroactive species better suited to the carbons with which they are used, and to improve energy storage in electrochemical supercapacitors.

The fast pyrolysis plant at RISE – ETC, Piteå produces carbon rich chars in bulk from various sources of biomass as feedstock. These in-house manufactured carbon rich chars were upgraded via pyrolysis as well as chemical activation using KOH to enhance their potential as an electrode material for supercapacitors. Commercial activated charcoal (Merck) was also studied and used as a yardstick for comparing performance of our materials. Investigations using EDX show enrichment in carbon content and very low amounts of impurities in the materials prepared from wood char after specific treatments for upgrading. Two-electrode coin cell apparatus with an aqueous electrolyte was used to determine the electrochemical performance of these materials. Wood char after KOH activation shows a high specific capacitance of ~105 Fg-1 at 2 Ag-1 in galvanostatic charge discharge measurements which outperformed activated charcoal used in this study (~68 Fg-1 at 2 Ag-1). This material was tested in a wide range of conditions (current density ranging from 0.1 Ag-1 to 10 Ag-1) and showed specific capacitance from ~90 Fg-1 (for 10 Ag-1) up to ~118 Fg-1 (for 0.1 Ag-1). Fatigue testing for &gt;20000 cycles showed a remarkably high retention (&gt;96%) of capacitance. Currently, most commercial supercapacitors use activated carbon materials prepared from coconut shells as the active electrode material which are not native to Sweden. In this study, we upgrade wood chars produced at RISE – ETC from biomass sources obtained locally (Sweden and Scandinavia) and demonstrate their applicability as supercapacitor electrode materials. / Den snabba pyrolysanläggningen vid RISE - ETC, Piteå, producerar kolrika kol i bulk från olika källor till biomassa som råvara. Dessa interna tillverkade kolrika karaktärer uppgraderades via pyrolys samt kemisk aktivering med hjälp av KOH för att förbättra deras potential som ett elektrodmaterial för superkondensatorer. Kommersiellt aktivt kol (Merck) studerades och användes som en måttstock för att jämföra våra materials prestanda. Undersökningar med EDX visar berikning av kolinnehåll och mycket låga mängder föroreningar i material som framställts av träkol efter specifika behandlingar för uppgradering. Tvåelektrodmyntcellapparater med en vattenhaltig elektrolyt användes för att bestämma den elektrokemiska prestandan hos dessa material. Träkol efter KOH-aktivering visar en hög specifik kapacitans på ~ 105 Fg-1 vid 2 Ag-1 i galvanostatiska laddningsurladdningsmätningar som överträffade aktivt kol som användes i denna studie (~ 68 Fg-1 vid 2 Ag-1). Detta material testades under ett stort antal betingelser (strömtäthet från 0,1 Ag-1 till 10 Ag-1) och visade specifik kapacitans från ~ 90 Fg-1 (för 10 Ag-1) upp till ~ 118 Fg-1 (för 0,1 Ag-1). Trötthetstestning för &gt; 20000 cykler visade en anmärkningsvärt hög retention (&gt; 96%) av kapacitansen. För närvarande använder de flesta kommersiella superkondensatorer aktivt kolmaterial framställt av kokosnötskal som det aktiva elektrodmaterialet som inte är hemma i Sverige. I den här studien uppgraderar vi träkolor som produceras vid RISE - ETC från biomassakällor erhållna lokalt (Sverige och Skandinavien) och visar deras användbarhet som superkapacitorelektrodmaterial.

No description available.

No description available.