WO2010032159A1

WO2010032159A1 - 2d or 3d electrochemical device employing composit active electrodes

Info

Publication number: WO2010032159A1
Application number: PCT/IB2009/053920
Authority: WO
Inventors: Willem Frederik Adrianus Besling; Rogier Adrianus Henrica Niessen; Johan Hendrik Klootwijk; Nynke Verhaegh
Original assignee: Nxp B.V.; Koninklijke Philips Electronics N.V.
Priority date: 2008-09-17
Filing date: 2009-09-08
Publication date: 2010-03-25

Abstract

The present invention relates to a modified rechargeable Li- ion solid- state battery design that is integrated in 3D silicon. Currently, several designs of 2D or 3D integrated batteries have already been described and disclosed in the prior art. Novel concepts (3D integration) of all- so lid- state rechargeable thin film Li-ion batteries were previously described in patent WO2005/O27245A2. These energy storage devices can be advantageously used as a power supply for many applications such as OLED devices, presence detection, implantables, smart cards and hearing aids. One of the problems associated with this type of solid-state batteries is the volume expansion/contraction of the active electrodes (anode and cathode) resulting from Lithium intercalation into/from the aforementioned electrodes. This volume change will inevitably cause stress and thus possibly compromise the mechanical stability of the device, resulting in lifetime degradation. Especially in high aspect ratio structures, like trenches, pillar or holes, high-curvature regions will cause problems. To reduce this volume expansion the active materials, comprising the anode and cathode, must be carefully chosen (chemical electrode matching) and their geometries matched (geometric electrode matching).

Description

2D OR 3D ELECTROCHEMICAL DEVICE EMPLOYING COMPOSIT ACTIVE ELECTRODES

FIELD OF THE INVENTION

The present invention relates to a modified electrochemical device such as a rechargeable Li-ion solid-state battery design that is preferably integrated in 3D silicon.

BACKGROUND OF THE INVENTION

Currently, several designs of 2D or 3D integrated batteries have already been described and disclosed in the prior art. Novel concepts (3D integration) of all- so lid- state rechargeable thin film Li-ion batteries were previously described in patent WO2005/O27245A2. These energy storage devices can be advantageously used as a power supply for many applications such as OLED devices, presence detection, implantables, smart cards and hearing aids.

One of the problems associated with this type of solid-state batteries is the volume expansion/contraction of the active electrodes (anode and cathode) resulting from Lithium intercalation into/from the aforementioned electrodes. This volume change will inevitably cause stress and thus compromise the mechanical stability of the device, resulting in lifetime degradation. Especially in high aspect ratio

(3D integrated) structures, like trenches, pillar or holes, high-curvature regions will cause problems. To reduce this volume expansion the active materials, comprising the anode and cathode, must be carefully chosen (chemical electrode matching) and their geometries matched (geometric electrode matching). These methods are described in patent application WO2008/075251A1 by Op het Veld et al.

Various authors have described research on the reduction of detrimental effects linked to volume expansion by altering stoichiometry/composition of many anode systems. This is, however, mainly limited to the alloying of common anode compounds with large volume expansion (e.g. silicon) with other metals (e.g.

United States Patent 7160646 Bl). Other disclosures are mentioned below.

EP 1463071 A2 discloses a layered ruthenic acid compound, which is converted to a protonic layered ruthenic acid hydrate, which is then converted to a layered alkylammonium-ruthenic acid intercalation compound to obtain a colloid containing ruthenic acid nanosheets having a thickness of 1 nm or smaller. Thereby, a ruthenic acid nanosheet is obtained. The material may be used in high power capacitors.

US2007/031732 Al discloses nanoscale ion storage materials that exhibit unique properties measurably distinct from their larger scale counterparts. For example, the nanoscale materials can exhibit increased electronic conductivity, improved electromechanical stability, increased rate of intercalation, and/or an extended range of solid solution. Useful nanoscale materials include alkaline transition metal phosphates, such as LiMPO₄, where M is one or more transition metals. The nanoscale ion storage materials are useful for producing devices such as high energy and high power storage batteries, battery-capacitor hybrid devices, and high rate electrochromic devices.

US2007/292763 Al discloses a method of manufacture an article of a cathode (positive electrode) material for lithium batteries. The cathode material is a lithium molybdenum composite transition metal oxide material and is prepared by mixing in a solid state an intermediate molybdenum composite transition metal oxide and a lithium source. The mixture is thermally treated to obtain the lithium molybdenum composite transition metal oxide cathode material. It is noted that this patent deals with bulk powder electrodes and not with thin film processed energy storage electrodes for (integrated) Li- ion batteries. This is regarded as a completely different class of elements.

The use of nano materials in intercalation cells is known per se. In all of the above disclosures, however, the mechanical stability and lifetime of the structures are jeopardized due to the use, and can not be maintained over time. Further many of the disclosures do not have a required performance, e.g. in terms of power supply.

Therefore, there still is a need for an improved electrochemical device such as a solid state battery, having a longer lifetime, as well as a good performance, e.g. in terms of power supply.

The present invention is aimed at solving the above problems.

SUMMARY OF THE INVENTION

The present invention relates to a 2D or 3D electrochemical device, comprising an anode, a cathode, an electrolyte comprising one or more components, wherein the cathode and/or anode comprise two or more materials selected from the group consisting of (nano) laminates, (nano) clusters, and (nano) cluster composites, and mixtures thereof, wherein at least one first material functions as an storage material for one or more components of the electrolyte, and wherein at least one second material is an electrochemically non-active material, wherein said first material has a different composition from said second material, a method of making the same, and use of said electrochemical device in an application.

The present electrochemical device, incorporating nanolaminates/nanoclusters, reduces the overall volume expansion/contraction of a composite such as thin film electrode for a micro power source. This is highly beneficial as, especially in a 3D integrated power source, extreme care has to be taken that expansion/contraction within the power source, such as a battery stack, does not lead to deterioration of performance.

DETAILED DESCRIPTION OF THE INVENTION In a first embodiment the present invention relates to a 2D or 3D electrochemical device, comprising an anode, a cathode, an electrolyte comprising one or more components, wherein the cathode and/or anode comprise two or more materials selected from the group consisting of (nano) laminates, (nano) clusters, and (nano) cluster composites, and mixtures thereof, wherein at least one first material functions as an storage material for one or more components of the electrolyte, and wherein at least one second material is an electrochemically non-active material, wherein said first material has a different composition from said second material.

The invention discloses a novel and improved way to mitigate and/or control the volume expansion occurring in electrochemical devices, such as solid-state (3D and 2D) battery stacks. In this way, the mechanical stability and lifetime of said in electrochemical devices can be maintained or vastly improved without sacrificing in performance.

In a preferred embodiment the present invention discloses a electrochemical device, such as a modified rechargeable solid-state battery design, that is either 2D or integrated in a 3D etched substrate such as silicon, porous alumina, germanium, metal (foil), Cu, Ta, etc. This modified design uses composite active battery electrodes, which comprise a mixture of (nano)laminate and/or (nano)clusters of two different materials, one being the storage (e.g. intercalation) material and one being a non-active material. The storage material functions as a - A - volume for one or more electrolyte species (components). The species may be stored in interstitial space, in interlayer space, in crystal structure in general, may form dislocations, or combinations thereof. As a consequence of the presence of a non- active material the present storage capacity is somewhat deteriorated compared to a device with only one material. However, the performance and integrity and stability over time are greatly improved, as is the reliability.

Typically the storage material comprises 20-99% of the anode and/or cathode volume available, preferably from 30-80%, more preferably from 40-75, such as from 50-70%. As mentioned above, the storage capacity should not be too small and should be readily accessible for electrolyte species. Therefore the volume of storage material should be as large as possible. On the other hand, the non-active material functions to keep the volume of the electrochemical device as constant as possible. Therefore, the volume of the non-active material should also be as large as possible. However, in a preferred embodiment the function of the storage material prevails over the function of the non-active material.

A battery is also meant to comprise one or more cells, each cell being formed according to any of the present claims.

The structure of the present device relates to an active and passive (non-active) material. The composition and structure of the anode and cathode, e.g. clusters, laminates, etc., are functionally interchangeable. Thus the anode may comprise the active and passive material, or the cathode may comprise both, or both the cathode and anode may comprise the active and passive (non-active) material. In a preferred embodiment the cathode comprises the active and passive material, in view of storage properties of the active material. Further, in a preferred embodiment, the anode comprises silicon, or a mixture of silicon and germanium.

Thus in the present invention the electrochemically inert (non-active) material (such as a passive oxide), i.e. an electrochemically stable material that is a non convertible material in a voltage region of operation, relates only to it's passive character in these terms, which material forms a combination with an electrochemically active material (i.e. intercalation compound) to arrive at a system with reduced volume expansion.

The term "nano" refers to a size in the order of 1-1000 nm, and in the present invention is also meant to encompass sizes in the order of 1 μm to 1000 μm, and even 1 mm to 100 mm. It preferably refers to sizes in the order of 1-1000 nm, as these sizes offer the best ratio of surface/volume of the materials in question.

In this design the storage material expands/contracts during device operation like an ordinary anode/cathode, but its expansion/contraction is being 'absorbed'/mitigated by an inert, volume-constant non active material. The overall effect of the composite electrode is a reduction in volume change, resulting in a more mechanically stable system. By tuning the ratio between the materials, as well as the type of nano-structure of the composite (i.e. nano-clusters, core-shell clusters, nano- laminate, etc.) the volume change can be controlled accordingly. It id extremely difficult to arrive as such designs, as most materials or combinations thereof do not form any of the present structures. Extensive research has been carried out to arrive at the present structures.

At present, an electrochemical energy source is present, characterized in that one or both the anode and the cathode of the battery are adapted for storage of species of the solid state electrolyte. Such species are selected from at least one of following elements: H, Li, Be, Mg, Cu, Ag, Na and K, and preferably Li. A suited electrolyte is LIPON. The electrochemically non-active material preferably conducts these species well, as well as other electrolytes, and preferably also electrons. As such, the performance of the matrix in terms of storage capacity and conductivity of an optionally generated current is further improved.

The at least one second material functions as a non-active material for the aforementioned species within the electrochemical potential range in which the intercalation/storage material is electrochemically active. Such second material is typically not an alloy. Thus, the present invention relates to use of a nanolaminate or nanoclustering or combination thereof to distinguish a passive matrix and an active electrode material. It is noted that this does not resemble a structure identical to any of those described in the prior art found. It is noted that the use of nano materials in intercalation cells is known, but is generally used to: - enhance active surface area of the electrode by means of self- assembly of storage materials onto bio-materials (WO2006/045076)

- reduce bulk effects like diffusion or poor electrical conductivity. This can be done by using very small nanoparticles (US2007/0031732) - enhance the melting/sintering properties of bulk powder electrodes (US2007/0292763); hence, the uses described above do not solve the problems of the present invention.

In a preferred embodiment the invention relates to a 2D or 3D electrochemical device according to claim 1, selected from the group consisting of integrated battery, energy storage device and power source, preferably an integrated battery, and/or wherein the electrolyte is an inorganic solid state electrolyte.

In a preferred embodiment the invention relates to a 2D or 3D electrochemical device, wherein the electrochemically non-active material is chosen from the group of compounds comprising one or more of a Group VIII metal. Even more preferably the electrochemically non-active material is chosen from the group of compounds comprising one or more of a Group VIII metal oxides, such as RuO₂, RhO₂, PdO₂, FeO₂, CoO₂, NiO₂, OsO₂, IrO₂, PtO₂, preferably RuO₂, Group VIII metal nitrides, Group VIII metal sulfides, Group VIII metal halides, and combinations thereof. It is found that specifically Group VIII metals, and compositions thereof, are suited, as these materials are stable, non-active, etc. in the range of operation.

The present embodiment is structurally firmer, and consists of relatively more electrochemically non-active material. Preferably RuO₂ is used, as it is a stable material, capable of withstanding volume changes, and providing a good mechanical stability over time. It is noted that both the cathode and anode material may be a matrix with RuO₂ particles embedded in it. Such an embodiment further provides a larger capacity per volume.

In a further preferred embodiment the invention relates to a 2D or 3D electrochemical device, wherein the electrochemically non-active material forms (nano) clusters around the storage material, or wherein the storage material forms (nano) clusters around the electrochemically non-active material, or wherein layers of storage material are alternated with layers of electrochemically non-active material, or wherein (nano) clusters of storage material and (nano) clusters of electrochemically non-active material are randomly mixed, and combination hereof. Various possibilities exist to alternate non-active material and storage material, each material occupying part of the volume available. The structures can be obtained by depositing layers, forming a laminate, or by co-deposition of materials under well defined conditions, thereby forming clusters of various forms, depending on conditions. The above structures are specifically related to the use of the materials according to the invention, e.g. a combination of a non-active material such as a Group VIII oxide and e.g. LiCoO₂. The formation of clusters, or laminates, occurs further at specific ratios between materials used. In a yet further preferred embodiment the invention relates to a 2D or

3D electrochemical device according to claim 5, wherein the size of the (nano) clusters is from 1-5000 nm, preferably from 2-250 nm, and/or wherein the layers have a thickness of 1-2000 nm, preferably 2-1000 nm, such as from 20-500 nm.

In a further preferred embodiment the invention relates to a 2D or 3D electrochemical device, having an electrolyte causing a volume change, wherein the electrolyte is preferably a material comprising Lithium, wherein the volume change is less than 3% upon storage (intercalation) or di-intercalation of electrolyte ions, preferably less than 2.5%, such as less than 2%.

In a further preferred embodiment the invention relates to a 2D or 3D electrochemical device, wherein the electrochemically non-active material conducts charge carriers such as Li and/or electrons well, preferably both. As such the non- active material contributes to properties of the present device, such as an improved conductivity.

In a further preferred embodiment the invention relates to a 2D or 3D electrochemical device, wherein the device further comprises one or more high aspect ratio structures, selected from trenches, pillar, holes and combinations thereof. An advantage of these 3D structures is that they increase the battery area. The 3D structures do preferably not act as electrodes or "active" part of the battery layer stack. Further, these 3D structures are mechanically and in operation stable, have a large surface to volume ratio, have improved power characteristics and improved lifetime, etc.

In a second aspect the invention relates to a method of forming a 2D or 3D electrochemical device according to the invention, comprising the steps of: providing a substrate; and applying an electrolyte by a technique such as co-deposition by physical vapor deposition, or co-evaporation, or alternating deposition by LPCVD or ALD, or by ink-jetting, or by sol-gel processing of mixed solutions, or spraying, or combinations thereof. In a third aspect the invention relates to a device, such as long-lifetime autonomous applications such as lighting control unit, a presence and motion detection device, a building (energy) control unit, an autonomous light source, green house sensor platform, wireless add-on sensors, medical implantable devices, OLED devices, presence detection, implantables, smart cards and hearing aids, comprising a 2D or 3D electrochemical device according to the invention.

The present invention is further elucidated by the following figures and examples, which are not intended to limit the scope of the invention. The person skilled in the art will understand that various embodiments may be combined.

BRIEF DESCRIPTION OF THE DRAWINGS

Fig. 1 shows a schematic part of a prior art solid state battery. Fig. 2 shows a schematic part of the present solid state battery. Fig. 3 shows a schematic part of the present solid state battery. Fig. 4 shows a schematic of the present solid state battery.

DETAILED DESCRIPTION OF THE DRAWINGS

Fig. 1 shows a schematic part of a prior art solid state battery. Therein a substrate (100) and a cathode (110) are shown. The cross-section of a common active electrode (in this case a well-known LiCoO₂ cathode is used) is shown. Here it is schematically depicted what will happen during lithium intercalation (expansion) and de-intercalation (contraction) under normal operating conditions of a rechargeable battery system employing this cathode. For this material a volume change (170) of 6 vol. % is expected between these two states. Such a volume change is undesired, in view of operating performance, e.g. charging, de charging, power delivery, and life time of the battery.

It should be mentioned here that the complete volume change during charge and discharge is a combined effect of both active electrodes, being the anode and cathode. It is evident that other cathode and anode materials result, of course, in other volume changes, some of them being much higher. For example, for cathodes:

- LiCoO₂ a Lio.₅Co0₂: ~6 vol. %

- Li₂NiO₂ a LiNiO₂ : ~ 18 vol. % And for anodes:

- SI a Li₂₂Si₅: -400 vol. %

- C a Li₆C: -13 vol. %

In order to reduce/mitigate the volume expansion of the cathode layer taken as an example in Fig. 1, it is the object of the invention to use a composite cathode system, comprising the electrochemically active LiCoO₂ part, as well as a non-active 'matrix' material.

Preferably the electrochemically non-active material conducts both lithium ions and electrons well. In this embodiment RuO₂ is chosen. This material is a good electronic conductor and known to show lithium ion conductivity, but is, however, not able to intercalate lithium ions at the electrochemical potential at which

LiCoO₂ stores/releases the bulk part of its lithium.

Fig. 2 shows a schematic part of the present solid state battery. Therein a substrate (200), at least one first material functions as an storage material (211) for one or more components of the electrolyte, and wherein at least one second material functions as a non-active matrix (210), wherein said first material has a different composition from said second material.

This composite cathode system can be realized in several different ways, these being: 1. A nanocluster system in which nanoclusters/nanoparticles of the active

LiCoO₂ material and the inactive RuO₂ material are randomly mixed on a nano-scale (figure 2a). Depending on the ratio of active and inactive material, more clusters of the active or more of the inactive material will be formed. Thus, figure 2a is not limited to the ratio between clusters of active and inactive material. The ratio of clusters active/inactive material may vary between 1 :10 and 10:1. Further, it is noted that clusters may vary in size, e.g. due to a natural process (such as statistics), due to the ratio mentioned, due to material properties etc.

2. A core-shell system in which nanoclusters/nanoparticles comprise an active LiCoO₂ core and an inactive RuO₂ shell, or vise versa. A typical size of said core-shell clusters is from 5-500 nm, preferably from 10-250 nm. The size of the clusters may be varied and controlled by changing the above ratio, the materials used etc. (see fig. 2c). The core shell clusters can have as a core an active material, and as a shell an inactive material, or vice versa. Fig. 2c shows a schematic drawing, however, in reality the clusters may have any form, e.g. substantially spherical, multigonal, etc. 3. A nano laminate system in which thin films of the active LiCoO₂ material and the inactive RuO2 material are alternated (on a nano-scale). The thickness of the films is from 5-500 nm, preferably from 10-250 nm (see fig. 2b). All these examples are shown in Fig.2. By introducing the second, inactive, material to the cathode, the volume expansion of the whole electrode (assembly) can be mitigated or, at least, controlled in order to reduce stress in the complete battery system. For the cathode part this is shown in Fig.3. which as indicated above, may equally well be the nano laminate solution as well as the given core-shell solution. Here the introduction of the RuO₂ 'matrix' material is able to reduce the volume change which is a value a lot lower that the sole cathode.

Fig. 3 shows a schematic part of the present solid-state battery. Therein a substrate (300), a storage material (311), and a non-active matrix (310) are shown. The cross-section of a nanocluster composite cathode system, comprising a LiCoO₂ active material (311) and a RuO₂ inactive material (310), in its lithiated (left) and de- lithiated state (right). For this material a volume change (370) of less than 4 vol.% is expected between these two states.

Another aspect of the invention is related to stress relaxation: if volume expansion due to lithiation or de-lithiation would result in local fracture of the composite material, the fracture energy of the tip will easily get absorbed within the composite material. In monolithic cathode and anode materials the fracture tip will continue through the whole film resulting in complete fracture.

Fig. 4 shows a schematic of the present solid-state battery, specifically a concept of a 3D solid-state micro battery. Therein a substrate (410), typically silicon is shown. Further a first current collector (400), typically forming part of the silicon substrate is shown. In Fig. 4b a patterned 3D or 2D layer is formed, preferably a silicon layer. In Fig. 4c further a barrier layer (420) is deposited on the pattern formed before. In Fig. 4d a cathode layer (430) is formed on top of the barrier layer. Thereon, in Fig. 4e a solid state electrolyte is deposited. Further, in Fig. 4f, an anode is deposited. Also, in Fig. 4g, a second current collector is provided.

The cathode material is typically deposited on top of the bottom current collector (basic metallic component typically Pt or Ru metal deposited by PVD or by ALD) with an underlying adhesion layers consisting of TiO₂, Ti and or TiN. All these materials can be deposited by PVD, CVD or ALD methods. Although feasible in 2D the alternating deposition of different cathode materials by PVD becomes even more complicated in 3D due to line of sight limitation in physical vapor deposition methods. This will result in films with poor step coverage and most probably also different film stoichio merries as function of depth. So for 3D applications a nanolaminated structure is advantageously deposited by Low Pressure Chemical Vapor Deposition (LPCVD) or Atomic Layer Deposition (ALD) which techniques are known to have much better step conformality and good control of stoichiometry on surfaces that have large topography. Just by changing/switching the metal containing precursor flows, the entire stack can be deposited inside, for example, a single CVD reactor chamber.

In one embodiment the growth of the active, Li-intercalating cathode material is carried out by Low-pressure CVD. The material comprises of e.g., LiMO₂ where M is a metal from the series of Co, Mn, or Ni and or combinations thereof.

A commercial horizontal cold walled LPCVD reactor (Aixtron 200RF) has been employed for the deposition of the LiCoO₂ cathode material, t-butyl lithium and Cobalt di-carbonyl cyclopentadienyl were used as precursors for respectively Li and Co upon using Ar as carrier gas to transport the vapor from the bubbler to the reactor. The Cobalt and lithium precursor were mixed with oxygen in the reaction chamber. Deposition temperatures are typically between 300 C and 500 C. For the deposition of RuO₂ Ruthenium cyclopentadienyl, Ru(Cp)₂ has been employed as Ru precursor source in combination with oxygen in a temperature range between 275 C and 450 C. Upon switching the precursor flows a nanolaminated stack can be grown of the two alternating materials. In order to maximize the capacity of the battery the thickness of the Li intercalating compound is preferably larger than the thickness of the inert matrix material.

The growth behavior of the matrix and intercalating cathode material on top of each other depends on the reactivity of the underlying substrate i.e. the density of reactive groups on the surface. If e.g. the RuO₂ matrix film is grown in a layer by layer fashion as is normally employed in Atomic Layer Deposition, the RuO₂ film tend to have difficulties to nucleate on the underlying substrate. If only very thin films are grown (i.e. a small number of growth cycles is applied) the RuO₂ film starts to grow in an island like fashion and remain discontinuous if not too thick films are grown. This typically occurs at higher deposition temperatures and/or the use of bulky ligands where steric hindrance start to play a role. At higher temperatures the density of-OH groups on the surface decreases, which will have an impact on the nucleation behavior of RuO₂ on the underlying LiCoO₂. If LPCVD growth of LiCoO₂ is continued before complete closure of the Ru film, a cathode material is obtained with nanodispersed RuO₂ particles embedded in them. Also the Lithium transition metal phosphates, LiMPO₄ M = Mn, Fe,

Co, Ni, with the olivine structure demonstrate reversible lithium extraction and insertion in LiFeP04 and can be used as active cathode material.

For the deposition Of LiFePO₄ the following precursors can be used as an example: t-butyl lithium (Lithium precursor), trimethylphosphate (phosphorous precursor) and ferrocene (bis( 5 cyclop entadienyl)iron) (Iron precursor). Deposition takes place at a temperature of 350 ⁰C.

The person skilled in the art is capable of adjusting flows, pressures, temperatures, growth velocities, etc. wherever relevant, to obtain the required characteristics.

Claims

CLAIMS:

1. 2D or 3D electrochemical device, comprising an anode, a cathode, an electrolyte comprising one or more components, wherein the cathode and/or anode comprise two or more materials selected from the group consisting of (nano) laminates, (nano) clusters, and (nano) cluster composites, and mixtures thereof, wherein at least one first material functions as an storage material for one or more components of the electrolyte, and wherein at least one second material is an electrochemically non-active material, wherein said first material has a different composition from said second material.

2. 2D or 3D electrochemical device according to claim 1, selected from the group consisting of integrated battery, energy storage device and power source, preferably an integrated battery, and/or wherein the electrolyte is an inorganic solid state electrolyte.

3. 2D or 3D electrochemical device according to claim 1 or claim 2, wherein the electrochemically non-active material is chosen from the group of compounds comprising one or more of a Group VIII metal.

4. 2D or 3D electrochemical device according to claim 3, wherein the electrochemically non-active material is chosen from the group of compounds comprising one or more of a Group VIII metal oxides, such as RuO₂, RhO₂, PdO₂, FeO₂, CoO₂, NiO₂, OsO₂, IrO₂, PtO₂, preferably RuO₂, Group VIII metal nitrides, Group VIII metal sulfides, Group VIII metal halides, and combinations thereof.

5. 2D or 3D electrochemical device according to any of claims 1-4, wherein the electrochemically non-active material forms (nano) clusters around the storage material, or wherein the storage material forms (nano) clusters around the electrochemically non-active material, or wherein layers of storage material are alternated with layers of electrochemically non-active material, or wherein (nano) clusters of storage material and (nano) clusters of electrochemically non-active material are randomly mixed, and combination hereof.

6. 2D or 3D electrochemical device according to claim 5, wherein the size of the (nano) clusters is from 1-5000 nm, preferably from 2-250 nm, and/or wherein the layers have a thickness of 1-2000 nm, preferably 2-1000 nm, such as from 20-500 nm.

7. 2D or 3D electrochemical device according to any of claims 1-6, having an electrolyte causing a volume change, wherein the electrolyte is preferably a material comprising Lithium, wherein the volume change is less than 3% upon intercalation or di-intercalation of electrolyte ions, preferably less than 2.5%, such as less than 2%.

8. 2D or 3D electrochemical device according to any of claims 1-7, wherein the electrochemically non-active material conducts charge carriers such as Li and/or electrons well, preferably both.

9. 2D or 3D electrochemical device according to any of claims 1-8, wherein the device further comprises one or more high aspect ratio structures, selected from trenches, pillar, holes and combinations thereof.

10. Method of forming a 2D or 3D electrochemical device according to any of claims 1-9, comprising the steps of:

- providing a substrate; and

- applying an electrolyte by a technique such as co-deposition by physical vapor deposition, or co-evaporation, or alternating deposition by LPCVD or ALD, or by ink jetting, or by sol-gel processing of mixed solutions, or spraying, or combinations thereof.

11. Device, such as long-lifetime autonomous applications such as lighting control unit, a presence and motion detection device, a building (energy) control unit, an autonomous light source, green house sensor platform, wireless add-on sensors, medical implantable device, OLED devices, presence detection, implantables, smart cards and hearing aids, comprising a 2D or 3D electrochemical device according to any of claims 1-9.