DE10215305A1 - Rechargeable lithium cells and batteries with active anode and cathode intercalation materials use electrolyte that is thermodynamically stable towards reduction at lithium-intercalated anode during operation - Google Patents

Abstract

In rechargeable lithium cells with improved cycle stability and good high current properties, consisting of an anode film with (A) an active anode intercalation material, a cathode film with (B) an active cathode intercalation material and an electrolyte, consisting of (C) electrolyte salt dissolved in (D) an electrolyte solvent, the electrolyte is thermodynamically stable towards reduction at the Li-intercalated anode during operation. Independent claims are also included for numerous versions of Li cells of this type with specified combinations of components.

Description

Previously rechargeable lithium cells have limited cycle stability.

Active cathode materials are used which have a high deintercalation voltage of approximately 4.2 V versus Li / Li ⁺ . LiCoO ₂ is widely used. LiCoO ₂ is a representative of the lithium transition metal oxide cathode materials with a layer structure, which have alternating layers of lithium and transition metal in a cubic, tightly packed oxygen lattice. The space group is R-3 m. The formula is Li _x M _y O ₂ where x ∼ 1 and y ∼ 1, and M is Ni, Co, Mn or mixtures of Ni, Co and / or Mn. Doping with Mg, Al or Ti is known. Other examples besides LiCoO ₂ are LiNiO ₂ or more precisely Li _1-x Ni _{1 + x} O ₂ (x ∼ 0.05), LiNi _1-x Co _x O ₂ , LiNi _1-xy Co _x Al _y O ₂ (x ∼ 0.2 , y ∼ 0.05, Li _{1 + x} {(Ni _1/2 Mn _1/2 ) _1-y Co _y } _1-x O ₂ (x ∼ 0.05, y ∼ 0.2) Another common cathode material is lithium manganese Spinel, not limited to stoichiometric spinel LiMn ₂ O _4. Particularly suitable are lithium-rich spinels, which can also be doped with other metals such as Al and other transition metals M such as Cr, Ni, Co, resulting in Li [Li _x M _y Mn _{2 -xy} ] O _2. Not all lithium-manganese spinels are 4 V cathode materials, for example LiNi _0.5 Mn _1.5 O ₄ has a voltage of about 4.85 V. In addition, cathode materials based on phosphates are known, lithium transition metal phosphate cathode materials are for example LiFePO ₄ , LiMnPO ₄ , LiFe _1-x Mn _x or LiCoPO _4. Phosphates with the olivine structure are preferred because they have a higher crystallographic density LiCoPO ₄ is a cathode material with a higher voltage versus Li / Li ⁺ . These phosphates can be modified by doping. Doping for the phosphate as well as for the transition metal is possible.

Hard carbons or graphite are used as active anode materials. These anode materials are used instead of lithium metal, which forms dendrites and thereby excessively reduces the electrolyte. Alternative anode intercalation materials such as lithium-titanium spinels, which have a higher voltage versus Li / Li ⁺ , are less common.

Electrolyte salts such as LiPF ₆ , dissolved in electrolyte solvents, are used as electrolytes. Typical electrolyte solvents contain molecules that can be cyclic or non-cyclic. Cyclic molecules such as EC (ethylene carbonate), PC (propylene carbonate), BC (butylene carbonate), GBL (gamma-butyrolactone), dioxalane and THF (tetrahydrofuran) can be opened by a reduction. Further examples of cyclic molecules are the corresponding sulfites such as ES (ethylene sulfite), PS (propylene sulfite) and others. Electrolytic solvents with non-cyclic molecules are, for example, DMC (dimethyl carbonate) and DEC (diethyl carbonate). Further examples are AN (acetonitrile) and the corresponding sulfites DMS and DES, furthermore DME (dimethoxyethane), EB (ethyl butyrate) and EMC (ethyl methyl carbonate). Electrolyte solvents are widespread, which are mixtures of cyclic carbonates, especially of EC (ethylene carbonates) with non-cyclic carbonates such as DEC (diethyl carbonate) or DMC (dimethyl carbonate). LiPF ₆ is mostly used as the electrolyte salt. LiPF ₆ is not stable in water. It is observed that LiPF ₆ , dissolved in electrolyte solvents, reacts with traces of water and possibly the solvent at elevated temperature. The stability of the salt in the solvent can be measured by suitable titration or analysis of the reaction products after storage at z. B. 60 ° C. In contrast, water-stable salts can be dissolved without reacting chemically with water.

During operation, lithium is intercalated into the anode and the voltage at the Carbon or graphite anode versus Li / Li + sinks and approaches 0V Leave the stability window of the electrolyte. Are on the surface of the anode at the same time Electrons, solvent molecules and lithium are present and the solvent will reduced. U.S. Patent No. 5,766,796 (K.M. Abraham & D. Peramunaga) describes that possible reduction of PC (propylene carbonates). The reduction of the solvent consumes lithium and results in a loss of reversible capacity. The Reaction products of the electrolyte reduction form a film on the anode, which is SEI (Solid Electrolyte Interface) is called.

If a suitable electrolyte is selected, the resulting SEI film is on the anode relatively stable. The SEI film is an electronic non-conductor. A stable SEI film separates the Electrolyte molecules from electrons and intercalated lithium. Therefore the Electrolyte reduction slows down. Only selected electrolytes form a relatively stable SEI Movie. SEI film-forming electrolytes are, for example, EC / DEC or EC / DMC. The addition from EC is particularly suitable for forming relatively stable SEI films. additional Film stabilizing additives are described, for example, in US Pat. No. 5,626,981 (Simon et al.) described. The stabilization of the SEI film is based on the preferred reduction of the Additives on the lithium intercalated anode. The real challenge, namely the Suppressing electrolyte reduction is not completely achieved.

This widespread access (carbon anode, SEI film-forming electrolytes, 4 V Cathode) is the conventional lithium-ion cell. The formation of a relatively stable SEI Films slows the electrolyte reduction rate, but the reduction is not completely prevented. The rate is small, but not zero. That is why Li-ion cells with carbon anodes have one limited cycle stability. Typically, at room temperature, up to 1000 cycles be cycled, however, will result in a loss of capacity and the building of high impedances observed. At higher temperatures (e.g. 55 ° C) the capacity loss rate is faster. The Loss is called fading and has several causes. (I) Loss of lithium at the anode by electrolyte reduction, (2) build-up of impedance layers on the cathode (3) destruction of the active electrode material, especially on the cathode. The electrolyte reduction at the Lithium intercalated anode (1) causes further problems such as B. (4) gas evolution before all during the first cycle, (5) reduced safety and (6) increased self-discharge.

The current technology of lithium-ion cells is not fully satisfactory Solution for the fading problem (1) - (3) and the other problems (4) - (6).

It has not been demonstrated in current technology that fading does so can be prevented that (1) is prevented or reduced.

Even when using alternative anode materials with a higher intercalation voltage, such as lithium titanium spinels, sufficient suppression of the electrolyte reduction at the lithium intercalated anode has not been demonstrated. Li ₄ Ti ₅ O ₁₂ and LiTi ₂ O ₄ are special representatives of the lithium-titanium spinels. The preparation, structure and electrochemical properties as well as the use of LiTi ₂ O ₄ and Li ₄ Ti ₅ O ₁₂ as cathode (versus lithium) in 1.5 V batteries is described in KM Colbow, JR Dahn, RR Haering, Journal of Power Sources 26 (1989) 397-402. The use as a cathode in 1.5 V batteries was patented by US 6,153,336 (Sanyo). The Japanese HEI HEI 6-275263 describes that lithium titanium oxides have excellent charge / discharge properties. The doctoral thesis "Lithium intercalation in titanium based oxides and sulfides" (PhD thesis by Kevin Colbow, University of British Colombia, 1988) describes a lithium cell which has Li ₄ Ti ₅ O ₁₂ as the anode and a 4 V intercalation material as the cathode. The use of Li ₄ Ti ₅ O ₁₂ as the anode has also been published in US 5,545,468 (Matsushita), US 5,591,546 (Matsushita) and US 6,274,271 (Matsushita). The US patent US 5,545,468 patents a rechargeable lithium cell, which has an lithium-titanium oxide as anode with a spinel crystal structure and a specific X-ray diffractogram. The patent focuses on LiTi ₂ O ₄ and Li ₄ Ti ₅ O ₁₂ , it is explained that the use of lithium titanium oxides allows to prevent dendrites. Improved cycle stability is demonstrated. The US patent US 5,591,546 publishes a rechargeable battery with lithium manganese spinel as the cathode and lithium titanium spinel as the anode. Both the cathode and the anode have a flat voltage characteristic, limited by sharp edges. These edges are used to avoid overcharge or underdischarge when cells are connected in series. The US patent US 5,591,546 publishes a rechargeable lithium battery which has Li ₄ Ti ₅ O ₁₂ or mixtures of Li ₄ Ti ₅ O ₁₂ with other materials as the anode. The preferred ratio of the anode to the cathode capacity is 0.8-1, which means that the lithium cells are anode-limited. Improved stability of the battery against overcharging or underdischarge is reported. None of the patents solve the problem of anode electrolyte reduction during operation. Specifically, it is not described that the use of an anode material with an intercalation voltage versus Li / Li ⁺ greater than 1 V, an electrolyte consisting of a water-stable electrolyte salt dissolved in an electrolyte solvent with non-cyclic molecules and a 4 V cathode material can solve the fading problem. Furthermore, no way is shown how batteries with good high current behavior and improved safety can be obtained.

The use of Li ₄ Ti ₅ O ₁₂ as anode material in lithium polymer batteries is described in US Pat. No. 5,766,796 (Abraham). The patent describes that a film with poor conductivity is deposited on carbon anodes in polymer batteries during operation at voltages versus Li / Li ⁺ below 1 V, which passivates the battery. It is described that the use of Li ₄ Ti ₅ O ₁₂ as an anode in a polymer battery with PAN gel electrolytes prevents the formation of the passivation film. LiClO ₄ , dissolved in a mixture of PC (propylene carbonate) and EC (ethylene carbonate), was used as the gelling component of the electrolyte. Both PC and EC are electrolyte solvents that are not made up of non-cyclic molecules. The data of the patent ( Fig. 5) show that a reduced but still significant fading is observed, and thus the fading problem is not solved. This is also demonstrated by Seok-Gyun Chang et all in Bull. Korean Chem. Soc. 2001 vol. 22 (5), pg. 481-487 confirms that they observe that PC is already reduced at about 1.8-2 V versus Li / Li ⁺ and that active lithium is lost. EC is even more unstable. Specifically, the cited invention does not show that the electrolyte reduction at the lithium intercalated anode can be sufficiently suppressed during operation if an anode material with an intercalation voltage versus Li / Li ⁺ greater than 1 V, an electrolyte consisting of a water-stable electrolyte salt dissolved in one Electrolyte solvent without EC consisting of non-cyclic molecules and a 4 V cathode material is used. Furthermore, US 5,766,796 does not demonstrate good high current behavior. The ratio of the capacities at C / 1 and C / 5 discharge is only about 0.9.

In addition to LiTi ₂ O ₄ or Li ₄ Ti ₅ O ₁₂ , modified lithium titanium oxide can also be used as the active anode material. US Pat. No. 6,221,531 (Vaughey) describes the modification of Li ₄ Ti ₅ O ₁₂ by doping with Mg, Al, Co, Ni etc. A possible advantage is that the modified materials have a higher electronic conductivity. Other possible modifications, such as. B. phase mixtures, surface modification, design of grain boundaries, certain morphologies, etc. are possible and known from the literature. The use of modified lithium titanium oxides by itself does not solve the fading problem.

Even when using improved cathode materials, such as. B. Modified lithium manganese spinel, the fading problem has not been solved. Lithium cells with a lithium manganese spinel cathode and improved cycle stability are described, for example, in US Pat. No. 5,084,366 (Matsushita). The patent reports that the use of modified spinels increases cycle stability. US Pat. No. 5,783,328 (Duracell) describes that the cycle stability of lithium cells with lithium-manganese spinel is improved, and the loss of capacity during storage can be reduced. The invention described is probably based on the fact that the normally used electrolyte salt LiPF _{6 is} not stable in contact with water. It reacts with water to form HF, LiF and POF ₃ gas.

HF reacts with Li ⁺ to LiF and a reactive proton. The proton could contribute to electrolyte reduction. It is also assumed that HF damages the cathodes (simplified HF + LiM ₂ O ₄ → LiF + HMn ₂ O ₄ ). It is therefore advantageous to reduce the proportion of HF in the lithium cell. A basic surface modification of the spinel is described, which functions as a proton trap. In the best case, the described cathode modifications reduce individual aspects of the fading problem, but do not solve it sufficiently because the essential cause, the electrolyte reduction at the anode, is not prevented.

In the current state of the art, no lithium batteries are known at very high rates (charge at 30C and discharge at 60C) at least 50% of the full Deliver energy density and at the same time allow high cycle stability. Loading and Discharge rates are defined as C rates. AC rate is the inverse of time in hours, which would be required to fully charge the cell at a given current density. 30C corresponds to a current density that the cell would fully charge in 2 minutes. such Charging and discharging rates with high cycle stability can be achieved with super capacitors can be achieved, however, their energy density is insufficient. That is why they are rechargeable Lithium batteries are desirable which are discharged and charged at very high rates can have a high energy density and a high cycle stability.

US Pat. No. 5,300,376 (EJ Plichta) describes the use of acetonitrile as an electrolyte solvent in order to achieve good high-current behavior. The patent describes simple oxides (WO ₂ or MoO ₂ ), sulfides or carbon as anodes. Lithium titanium oxide is not mentioned. LiCoO ₂ and LiNiO _{2 are} published as cathodes, but not Li-Mn spinel. The inventor does not focus on cathodes and anode materials that enable good high current behavior. It is specifically not described that the intercalation voltage at the anode must be greater than 1 V versus Li / Li ⁺ (that of the carbon is smaller) and that water-stable electrolyte salt must be used to reduce the electrolyte at the lithium intercalated anode during the Avoid operation. Therefore, the mentioned invention does not demonstrate a lithium cell with good cycle stability, reduced electrolyte reduction at the lithium intercalated anode and, at the same time, good high current behavior.

Good high-current behavior with high cycle stability requires an electrolyte with a sufficiently high ionic conductivity and simultaneous stability of the electrolyte against reduction at the lithium intercalated anode during operation. Examples of the prior art use solvents with high ionic conductivity, which also form relatively stable SEI films on the anode. The US patent US 4,737,424 (NTT) describes, for example, lithium cells with electrolyte solvents, such as EC / THF, EC / AN or EC / diethoxyethane. These electrolytes do not prevent the reduction at the anode, because of the EC content they form relatively stable SEI films. US 4,737,424 (NTT) focuses on amorphous cathodes and lithium metal as the anode. Lithium metal has a voltage of OV versus Li / Li ⁺ . At this voltage, none of the above-mentioned electrolytes is stable against reduction. US Pat. No. 4,770,959 (Daiking Kogyo) describes an electrolyte which is LiPF ₆ dissolved in a mixture of gamma-butyrolactone and acetonitrile. The electrolyte allows improved high-current behavior in lithium cells which have a Li metal anode and a fluorocarbon cathode. In this case, too, the electrolyte reduction at the anode is not prevented.

The invention presented here solves the fading problem.

The invention is based on the fact that (2) and (3) can be prevented or greatly reduced if (1) is prevented or reduced. The invention relates to rechargeable lithium cells with improved cycle stability and good high current behavior, used in rechargeable lithium batteries. The lithium cells consist of an anode film, an electrolyte and the cathode film. The improved cycle stability is achieved by using an electrolyte and an anode, which according to the invention are characterized in that the electrolyte is stable with respect to the reduction at the lithium-intercalated anode. In particular, the anode film contains an active anode intercalation material with a voltage versus Li / Li ⁺ greater than 1 V, preferably ∼ 1.5 V, such as Li ₄ Ti ₅ O ₁₂ . The electrolyte is a water-stable electrolyte salt dissolved in an electrolyte solvent which is free of ethylene carbonate and preferably consists of non-cyclic molecules such as acetonitrile or dimethyl carbonate. The cathode film contains a cathode intercalation material with a voltage versus Li / Li ⁺ greater than 3.5 V, preferably ∼ 4.2 V, such as lithium-manganese spinel. It is preferred that the lithium cells are cathode limited. The battery can be charged at a high rate without kinetic lithium deposition occurring. A preferred implementation of the invention are large rechargeable lithium batteries, consisting of stacks of bipolar plates connected in series, and lithium batteries with very good high-current behavior. Such batteries can be charged at 30C rates for at least 1 minute and discharged at 60C rates for at least 30 seconds, the respective working voltage deviating less than 20% from the corresponding voltage of the same charge state at a slow rate.

Individual aspects of the invention are explained in more detail below:
Surprisingly, the stability of the electrolyte against reduction at the lithium-intercalated anode during operation is greatly improved if a lithium cell is used which uses a 1.5 V material such as Li ₄ Ti ₅ O ₁₂ as the anode material and a water-stable electrolyte salt such as Li-BETI or LiBF ₄ , dissolved in an electrolyte solvent, consisting of non-cyclic molecules such as DMC or acetonitrile, and containing a 4 V material such as Li-Mn spinel as the active cathode material. Problems (1) - (6) are thus solved or at least greatly reduced in comparison to current technology. In a special implementation of the current invention, a greatly improved high-current behavior with high cycle stability compared to the prior art is demonstrated if a lithium cell is used which uses a 1.5 V material such as Li ₄ Ti ₅ O ₁₂ as the anode material and a water-stable electrolyte salt as the electrolyte LiBF ₄ dissolved in an electrolyte solvent, consisting of non-cyclic molecules such as aztonitrile, and containing a 4 V material such as Li-Mn spinel as the active cathode material.

Batteries with low self-discharge are desirable. Self-discharge is through Side reactions caused. The main side reaction is the reduction of the electrolyte the lithium intercalated anode. Batteries with low gas generation are desirable. The gas evolution becomes essential through the reduction of the electrolyte at the Lithium intercalated anode caused. Batteries with high security are desirable, especially with thermal load. A catastrophic event is when a battery is used "thermalrunaway" is coming. The "thermal runaway" arises when exothermic reactions affect the battery heat up, which speeds up the reaction rate of the exothermic reactions. Ultimately, can the battery explode. The exothermic reaction rates can be determined by the Heat development in an ARC (Accelerating Rate Coulometer) under adjabatic Conditions is measured. Specifically, the reactivity of the lithium deintercalated Cathode or the lithium intercalated anode measured in contact with the electrolyte become. An electrochemical cell has increased safety properties when charged Cell shows low reactivity at elevated temperature. The first exothermic Reaction is the reduction of the electrolyte at the lithium intercalated anode, which "thermal runaway" triggers. Batteries with high cycle stability are desirable. A The main reason for the loss of reversible capacity is the loss of active Lithium through electrolyte reduction at the lithium intercalated anode. Another cause is the decay of the cathode. Reaction products of the electrolyte reduction take part in the Destruction of the cathode material. Batteries without the construction of are desirable Polarization or impedance films. A major cause of impedance films are Reaction products of the electrolyte reduction on the lithium intercalated anode, which are used for Diffuse cathode and deposit there as films with poor conductivity. It can be summed that suppression of electrolyte reduction intercalated on the lithium Anode reduces self-discharge, gas evolution and cathode degradation, safety and improved cycle stability, and reduced build-up of impedance films.

Preferred anode materials have a deintercalation voltage versus Li / Li ⁺ between 1-2 V, they must also have a high capacity, good cycle stability and good kinetics. If the voltage is lower, the electrolyte reduction at the lithium intercalated anode is not sufficiently suppressed. If the voltage is higher, the energy density of the lithium cell decreases too much. Li ₄ Ti ₅ O ₁₂ is a particularly preferred anode material with a voltage versus Li / Li ⁺ of 1.57 V, the capacity of 170 mAh / g and the good kinetics.

Batteries with good high current behavior are desirable. For this purpose, (1) an electrolyte with high ionic conductivity, (2) a cathode material with good kinetics, (3) an anode material with good kinetics, (4) an anode material with increased voltage versus Li / Li ⁺ and (5) a suitable electrode morphology necessary. At the same time, the electrolyte must be stable against electrolyte reduction at the lithium intercalated anode. Particularly preferred electrolytes are LiBF ₄ in acetonitrile or Li-BETI in DMC. A preferred cathode material with good kinetics is modified lithium-manganese spinel; lithium-rich spinel Li [Li _x Mn _1-xy M _y ] O ₂ is particularly preferably additionally doped with Cr, Ni or Co. A preferred anode material with good kinetics is Li ₄ Ti ₅ O ₁₂ . Due to the increased voltage of 1.57 V versus Li / Li ^+, this material allows high battery charging rates, without the voltage, caused by polarization of the electrolyte at the anode, dropping locally below zero, which causes undesired lithium deposition or kinetic electrolyte reduction. The kinetics of the active cathode and anode material largely depend on the BET surface. The BET surface area of an active cathode or anode material corresponds (if no nanopores are present) to approximately the surface area that can be wetted by the electrolyte. The BET surface area is measured by gas adsorption. Since the typical time for lithium transport is proportional to the square of the typical diffusion length, materials with small primary particles and thus a larger BET surface allow better kinetics. On the other hand, a BET surface area that is too large increases the area where undesired side reactions can take place. The thickness, porosity and turtoisity of the anode and cathode films also determine the high current behavior. If the lithium transport in the electrolyte is rate-limiting, then thicker electrodes increase the power density per cm ² , while thinner electrodes increase the power per mass of active material. Porosities that are too small slow down the camouflage of lithium in the electrolyte, porosities that are too large reduce the energy density. The tourism should be as small as possible.

Depending on the application, different cathode materials may be preferred. Batteries with higher energy density are achieved when using cathode materials with high capacity or with high voltage versus Li / Li ⁺ . A preferred material with high capacity is Li _x M _y O ₂ with a layered crystal structure with x ∼ y ∼ 1 and M consisting essentially of Co, Ni and / or Mn, such as. B. LiCoO ₂ , LiNi _0.8 Co _0.2 O ₂ or Li [Li _0.05 {(Ni _1/2 Mn _1/2 ) _5/6 Co _1/6 }] O ₂ . Preferred materials with high tension are modified spinels such as LiMn _1.5 Ni _0.5 O ₄ or olivine phosphates such as LiCoPO ₄ . Preferred cathode materials for batteries with very high security are olivine phosphates such as LiFePO ₄ . Modified lithium manganese spinel is preferred for batteries with very good high current behavior and high safety. Furthermore, a lithium cell with a modified lithium manganese spinel cathode and lithium titanium spinel anode shows a flat voltage characteristic delimited by sharp edges.

This characteristic is advantageous in order to overcharge or underdischarge cells in series are to be avoided.

Lithium cells can be anode limited, cathode limited or "balanced". To the To avoid electrolyte reduction at the lithium intercalated anode, it is advantageous that the Anode is never completely saturated with lithium. That is accomplished by the cell is cathode limited. A particularly preferred ratio of the cathode capacity to Anode capacity is 0.7-0.95. The cathode to anode capacity ratio is the quotient of the specific lithium deintercalation capacity of the cathode material multiplied by the Cathode loading and the specific lithium intercalation capacity of the anode material multiplied by the anode load.

In cathode-limited cells, the reversible capacity decreases when active lithium is lost due to the electrolyte reduction at the lithium intercalated anode. Therefore have lithium cells, which have a high cycle stability, a high stability of the Electrolyte against reduction at the anode. That is not the case if the cell is anode limited, or the cathode has a large irreversible capacity. Such a cell can (until the additional lithium of the cathode is used up) a high cycle stability for a have a limited number of cycles. However, that does not mean that the Electrolyte reduction at the lithium intercalated anode is prevented. With such cells gas development and high self-discharge possible despite the cycle stability.

Suitable electrolytes are liquid electrolytes or gel polymers gelled with a liquid electrolyte. Electrolytes which have a high stability towards reduction at the lithium intercalated anode are preferred. Such electrolytes consist of an electrolyte solvent without EC (ethylene carbonates) and a water-stable electrolyte salt. Typical examples of electrolyte solvents are PC, DMC, DEC, EMC or tetrahydrofuran (THF), as well as γ-butyrolactones or nitriles such as acetonitrile (AN). Solvents with non-cyclic molecules such as DMC or AN are particularly preferred. In contrast to cyclic molecules, non-cyclic molecules cannot be reduced by ring opening. Preferred water-stable electrolyte salts are, for example, LiBF ₄ , Li-BETI (LiN (SO ₂ C ₂ F ₅ ) ₂ , LiClO ₄ or LIPAF (LiPF ₃ (C ₂ F ₅ ) _3. Non-stable salts such as LiPF ₆ are avoided.

The anode or cathode films contain the active electrode material typically binders such as PVDF or PVDF-HFP or SBR or EPDM Lead additives, typically carbon black or graphite. If a liquid electrolyte is used, it is advantageous to add small concentrations of binder and lead additives use. This increases the porosity, which increases transport in the liquid electrolyte improved. Furthermore, larger amounts of soot or graphite would cover the surface which side reactions can take place increase too much.

In normal lithium-ion cells, the substrate for the anode is copper and the substrate for the cathode is aluminum. If anode materials such as Li ₄ Ti ₅ O ₁₂ with an intercalation voltage versus Li / Li ⁺ greater than 1 V are used according to the invention, aluminum can also be used for the anode. In this case it is possible to use bipolar plates. The anode and cathode films are congruent on opposite sides of the aluminum substrate. To achieve higher voltages, stacks of bipolar plates, separated from an electrolyte, can be connected in series. Large batteries are possible due to the high security of lithium cells with Li ₄ Ti ₅ O ₁₂ anodes. Large batteries advantageously consist of stacks of 5-100 bipolar plates with a large area of 100-4000 cm ² . A reduced contact resistance between metal substrates and electrode film can be achieved by "priming" z. B. By coating the metal substrate with thin layers of soot or graphite.

In the following, selected aspects of the invention are demonstrated in examples.

example 1

• - das aktive Anoden Material Li₄Ti₅O₁₂ mit einer BET-Oberfläche von 2.6 m²/g ist,
• - das aktive Kathoden-Interkalationsmaterial Li[Li_x(Cr_0.05Mn_0.95)_1-x]O₄ (x ∼ 0.03) mit einer BET-Oberfläche von 3 m²/g ist
• - der Elektrolyt ein 1M Elektrolytsalz gelöst in einem Elektrolyt-Lösungsmittel ist, wobei
  das Lösungsmittel Acetonitril bzw. Dimethylkarbonat ist und
  das Elektrolytsalz LiBF₄ bzw. Li-BETI (LiN(C₂F₅SO₂)₂) ist,

wobei der Kathodenfilm eine Beladung von 20 mg/cm² hat und das Kathoden- zu Anodenkapazitätsverhaltnis 0.9 ist. Table 1A shows results for long-term cycling of 2 types of lithium cells consisting of an anode film with an active anode intercalation material, a cathode film with an active cathode intercalation material and an electrolyte consisting of an electrolyte salt dissolved in an electrolyte solvent. The cells are characterized in that

• the active anode material is Li ₄ Ti ₅ O ₁₂ with a BET surface area of 2.6 m ² / g,
• - The active cathode intercalation material is Li [Li _x (Cr _0.05 Mn _0.95 ) _1-x ] O ₄ (x ∼ 0.03) with a BET surface area of 3 m ² / g
• - The electrolyte is a 1M electrolyte salt dissolved in an electrolyte solvent, whereby
  the solvent is acetonitrile or dimethyl carbonate and
  the electrolyte salt is LiBF ₄ or Li-BETI (LiN (C ₂ F ₅ SO ₂ ) ₂ ),

wherein the cathode film has a loading of 20 mg / cm ² and the cathode to anode capacity ratio is 0.9.

Because the cells are n cathode limited, the rate of reversible capacity loss is a measure of the rate of electrolyte reduction at the lithium intercalated anode. To increase the reduction rate, the batteries were cycled at 55 ° C. A single cycle took about 4 hours. Table 1A Long-term cycling of lithium cells at 55 ° C. Capacities are per g of active cathode material

Comparative Example 1

• - das aktive Anoden Material Li₄Ti₅O₁₂ mit einer BET-Oberfläche von 2.6 m²/g ist,
• - das aktive Kathoden-Interkalationsmaterial Li[Li_x(Cr_0.05Mn_0.95)_1-x]O₄ (x ∼ 0.03) mit einer BET-Oberfläche von 3 m²/g ist
• - der Elektrolyt ein 1M Elektrolytsalz gelöst in einem Elektrolyt-Lösungsmittel ist wobei
  das Lösungsmittel zyklische Moleküle enthält oder
  das Elektrolytsalz nicht wasserstabil ist,

wobei der Kathodenfilm eine Beladung von 20 mg/cm² hat und das Kathoden- zu Anodenkapazitätsverhaltnis 0.9 ist. Table 1B shows results for long-term cycling of 2 types of lithium cells consisting of an anode film with an active anode intercalation material, a cathode film with an active cathode intercalation material and an electrolyte consisting of an electrolyte salt dissolved in an electrolyte solvent. The cells are characterized in that

• the active anode material is Li ₄ Ti ₅ O ₁₂ with a BET surface area of 2.6 m ² / g,
• - The active cathode intercalation material is Li [Li _x (Cr _0.05 Mn _0.95 ) _1-x ] O ₄ (x ∼ 0.03) with a BET surface area of 3 m ² / g
• - The electrolyte is a 1M electrolyte salt dissolved in an electrolyte solvent
  the solvent contains cyclic molecules or
  the electrolyte salt is not water-stable,

wherein the cathode film has a loading of 20 mg / cm ² and the cathode to anode capacity ratio is 0.9.

Because the cells are cathode limited, the rate of reversible capacity loss is a measure of the rate of electrolyte reduction at the lithium intercalated anode. To increase the reduction rate, the batteries were cycled at 55 ° C. A single cycle took about 4 hours. Table 1B Table 1A Long-term cycling of lithium cells at 55 ° C. Capacities are per gram of active cathode material

Comparison of Figure 1A with Figure 1B shows that the rate of electrolyte reduction at the lithium intercalated anode according to the invention is greatly reduced when non-cyclic electrolyte solvents and water stable salts are used. In contrast, the electrolyte reduction at the lithium intercalated anode is not sufficiently suppressed when a non-water-stable salt such as LiPF ₆ or a solvent with cyclic molecules is used.

Example 2

• - das aktive Anoden Material Li₄Ti₅O₁₂ mit einer BET-Oberfläche von 2.6 m²/g ist,
• - das aktive Kathoden-Interkalationsmaterial Li[Li_x(Cr_0.05Mn_0.95)_1-x]O₄ (x ∼ 0.03) mit einer BET-Oberfläche von 3 m²/g ist
• - der Elektrolyt ein 1M Elektrolytsalz gelöst in einem Elektrolyt-Lösungsmittel ist, wobei
  das Lösungsmittel Acetonitril ist und
  das Elektrolytsalz LiBF₄ ist,

wobei der Kathodenfilm eine Beladung von 12 mg/cm² hat und das Kathoden- zu Anodenkapazitätsverhältnis 0.9 ist. Tabelle 2 Technische Daten der Lithiumzelle erhalten während verschiedener konstanter Entladeströme. Eine 1C-Rate war definiert als 100 mA je Gramm aktivem Kathodenmaterials. Spezifische Daten sind per Gramm aktiven Kathodenmaterials

Table 2 shows technical data of a rechargeable lithium cell consisting of an anode film with an active anode intercalation material, a cathode film with an active cathode intercalation material and an electrolyte consisting of an electrolyte salt dissolved in an electrolyte solvent. The cell is characterized in that

• the active anode material is Li ₄ Ti ₅ O ₁₂ with a BET surface area of 2.6 m ² / g,
• - The active cathode intercalation material is Li [Li _x (Cr _0.05 Mn _0.95 ) _1-x ] O ₄ (x ∼ 0.03) with a BET surface area of 3 m ² / g
• - The electrolyte is a 1M electrolyte salt dissolved in an electrolyte solvent, whereby
  the solvent is acetonitrile and
  the electrolyte salt is LiBF ₄ ,

wherein the cathode film has a loading of 12 mg / cm ² and the cathode to anode capacity ratio is 0.9. Table 2 Technical data of the lithium cell obtained during various constant discharge currents. A 1C rate was defined as 100 mA per gram of active cathode material. Specific data are per gram of active cathode material

The rechargeable lithium cell of the example reaches 76% of the energy density (compared to the Energy density with slow 2C discharge) with a constant discharge current of 5300 mA each Grams of active cathode material which corresponds to a 53C rate. The discharge current of 5300 mA / g could be maintained for 59.8 seconds until the lower voltage of 1.5 V was undercut. 88% of the capacity (compared to the capacity (mAh / g) was added slow 2C discharge) reached. The specific power density (power per active Cathode mass) achieved at 53C was 11.5 kW / kg.

Example 3A

Calculation of the energy and power density of a rechargeable lithium battery. The lithium battery consists of stacks of bipolar plates separated by electrolyte-filled separators. Table 3A shows the data used. Table 3A Lithium battery

With an operating voltage of 2.5 V and slow discharge, an energy density of approximately 80 Wh / kg or 190 Wh / dm ^{3 is} achieved, the capacity is 30 Ah / kg or 80 Ah / dm ³ . The information is for a large battery without taking into account the housing, current collectors, seals etc. If an energy density of 50% is assumed for a 60C discharge, the power density is 2.4 kW / kg or 5.8 kW / dm ³ . Under these conditions, the 60C rate discharge is maintained for more than 30 seconds.

Comparative Example 3B

Calculation of the energy and power density of a supercapacitor. The supercapacitor consists of stacks of bipolar plates with activated carbon electrodes separated by an electrolyte-filled separator. Table 3B shows the data used. Table 3B) Supercapacitor

The capacitor is charged up to 2.5 V. This results in a specific energy density of 9 Wh / kg or 14 Wh / dm ³ . The information is for a large battery without taking into account the housing, current collectors, seals, etc.

The comparison of FIGS. 3A and 3B shows that the lithium battery can support the power density of 2.4 kW / kg or 5.8 kW / dm ³ for more than 30 seconds, while the theoretical supercapacitor has the same power densities for a maximum of only 15 seconds (gravimetric ) or 9th seconds (volumetric). In practice, a supercapacitor will only be able to support the power densities for much shorter times, since 100 F / g is a very high electrode capacity and other practically unavoidable energy losses were not taken into account.

Example 4

• - das aktive Anoden Material Li₄Ti₅O₁₂ mit einer BET-Oberfläche von 2.6 m²/g ist,
• - das aktive Kathoden-Interkalationsmaterial Li[Li_x(Cr_0.05Mn_0.95)_1-x]O₄ (x ∼ 0.03) mit einer BET-Oberfläche von 3 m²/g ist
• - der Elektrolyt ein 1M Elektrolytsalz gelöst in einem Elektrolyt-Lösungsmittel ist wobei
  das Lösungsmittel Acetonitrile ist und
  das Elektrolytsalz LiBF₄ ist,

wobei der Kathodenfilm eine Beladung von 12 mg/cm² hat und das Kathoden- zu Anodenkapazitätsverhaltnis 0.9 ist. Table 4 shows data on the cycle stability of a rechargeable lithium cell during long-term cycling at high rates. The cell consists of an anode film with an active anode intercalation material, a cathode film with an active cathode intercalation material and an electrolyte consisting of an electrolyte salt dissolved in an electrolyte solvent. It is characterized in that

• the active anode material is Li ₄ Ti ₅ O ₁₂ with a BET surface area of 2.6 m ² / g,
• - The active cathode intercalation material is Li [Li _x (Cr _0.05 Mn _0.95 ) _1-x ] O ₄ (x ∼ 0.03) with a BET surface area of 3 m ² / g
• - The electrolyte is a 1M electrolyte salt dissolved in an electrolyte solvent
  the solvent is acetonitrile and
  the electrolyte salt is LiBF ₄ ,

wherein the cathode film has a loading of 12 mg / cm ² and the cathode to anode capacity ratio is 0.9.

The lithium cells of Example 2 were further cycled at 20 ° C. 15C was selected as the charging current and 30C as the discharging current. After each charge and discharge, the battery was idle for 5 minutes. Each cycle lasts about 15 minutes. The capacity was determined in both cases with slow charge (0.75C) and discharge (1.5C) as well as with very fast charge (30C) and discharge (60C). Table 4 Long-term cycling of a lithium cell with good high current behavior

The results show a high cycle stability while maintaining a for more than 1000 cycles excellent high current behavior. Since the cells are cathode limited, the reached shows Cycle stability that the reduction of the electrolyte at the lithium intercalated anode greatly is suppressed.

Example 5

• - das aktive Anoden Material Li₄Ti₅O₁₂ mit einer BET-Oberfläche von 2.6 m²/g ist,
• - das aktive Kathoden-Interkalationsmaterial Li[Li_x(Cr_0.05Mn_0.95)_1-x]O₄ (x ∼ 0.03) mit einer BET-Oberfläche von 3 m²/g ist
• - der Elektrolyt ist 1M Elektrolytsalz gelöst in einem Elektrolyt-Lösungsmittel ist wobei
  das Lösungsmittel DMC (Dimethylkarbonat) ist und
  das Elektrolytsalz Li-BETI (LiN(C₂F₅SO₂)₂) ist,

wobei der Kathodenfilm eine Beladung von 20 mg/cm² hat und das Kathoden- zu Anodenkapazitätsverhaltnis 0.9 ist. Tabelle 5A Hochstromverhalten einer Lithiumzelle mit 1M LiBF₄ in DMC

Table 5 shows data on the high-current behavior of a rechargeable lithium cell consisting of an anode film with an active anode intercalation material, a cathode film with an active cathode intercalation material and an electrolyte consisting of electrolyte salt dissolved in an electrolyte solvent. The cell is characterized in that

• the active anode material is Li ₄ Ti ₅ O ₁₂ with a BET surface area of 2.6 m ² / g,
• - The active cathode intercalation material is Li [Li _x (Cr _0.05 Mn _0.95 ) _1-x ] O ₄ (x ∼ 0.03) with a BET surface area of 3 m ² / g
• - The electrolyte is 1M electrolyte salt dissolved in an electrolyte solvent
  the solvent is DMC (dimethyl carbonate) and
  the electrolyte salt is Li-BETI (LiN (C ₂ F ₅ SO ₂ ) ₂ ),

wherein the cathode film has a loading of 20 mg / cm ² and the cathode to anode capacity ratio is 0.9. Table 5A High current behavior of a lithium cell with 1M LiBF ₄ in DMC

For comparison, Table 5B shows results on the high-current behavior of a corresponding lithium cell but with 1M LiPF ₆ in PC (propylene carbonate) electrolyte.

Comparison of the data from Tables 5A and 5B shows that the high current behavior of the lithium cell with the 1M Li-BETI in DMC electrolytes is better than that of a cell with 1M LiPF ₆ in PC electrolytes.

Example 5 safety

The reduction of the electrolyte at the lithium intercalated Li ₄ Ti ₅ O ₁₂ anode during thermal stress was measured by means of ARC (Accelerating rate Coulometry) under adjabatic conditions. The Li ₄ Ti ₅ O ₁₂ anode was fully lithium intercalated (> 160 mAh / g). The measuring principle is described in M. Richard, J. Dahn J. Electroch. Soc. 146 (1999), 2068 and in J. Electroch. Soc. 146 (1999), 2078. No self-sustaining exothermic reactions were detected up to approximately 190 ° C. A small exothermic reaction starts at around 210 ° C and increases the temperature by less than 20K. The result shows that the electrolyte reduction at the lithium intercalated anode is strongly suppressed.

In comparison, the literature (2B. Richard, Dahn in J. Power Sources 83 (1999) 71 or Richard, Dahn in J. Electroch. Soc. 146 (1999), 2068 or J. Electroch. Soc. 146 (1999), 2078) reports that lithium-intercalated graphite in contact with electrolyte already at around 90 ° C shows strong exothermic reactions which lead to "thermal runaway". For graphite, for example semi-intercalated with lithium (0.127 V), causes the exothermic starting at about 90 ° C Response a temperature increase of about 60K.

Claims (23)

1. Rechargeable lithium cell with improved cycle stability and good high current behavior, consisting of an anode film with an active anode intercalation material, a cathode film with an active cathode intercalation material and an electrolyte, consisting of an electrolyte salt, dissolved in an electrolyte solvent, characterized in that the electrolyte is thermodynamically stable against reduction at the lithium-intercalated anode during operation. 2. Rechargeable lithium cell with improved cycle stability and good high-current behavior, consisting of an anode film with an active anode intercalation material, a cathode film with an active cathode intercalation material and an electrolyte, consisting of an electrolyte salt, dissolved in an electrolyte solvent, characterized in that
the anode, intercalated with lithium, has a voltage versus Li / Li ⁺ greater than 1 V,
the cathode, lithium deintercalated, has a voltage versus Li / Li ⁺ greater than 3.5 V,
the electrolyte solvent is free of EC (ethylene carbonate) and
the electrolyte salt is stable in water. 3. Rechargeable lithium cell with improved cycle stability and good high current behavior, consisting of an anode film with an active anode intercalation material, a cathode film with an active cathode intercalation material and an electrolyte, consisting of an electrolyte salt, dissolved in an electrolyte solvent, characterized in that
the anode, intercalated with lithium, has a voltage versus Li / Li ⁺ greater than 1 V,
the cathode, lithium deintercalated, has a voltage versus Li / Li ⁺ greater than 3.5 V,
the electrolyte solvent consists of non-cyclic molecules and
the electrolyte salt is stable in water. 4. Rechargeable lithium cell with improved cycle stability and good high-current behavior, consisting of an anode film with an active anode intercalation material, a cathode film with an active cathode intercalation material and an electrolyte consisting of an electrolyte salt, dissolved in an electrolyte solvent, characterized in that
the active anode material is a lithium M-oxide, which has the spinel structure as the crystal structure, at least 90% of the metal M being transition metal and at least 75% of the metal M being titanium,
the active cathode intercalation material is one or more selected from
a lithium M-oxide which has the spinel structure, at least 90% of the metal M being transition metal and at least 75% of the transition metal being manganese,
a lithium transition metal phosphate which has the olivine structure or
a lithium M-oxide, which has a layer structure (R-3 m), at least 90% of the metal M being transition metal,
the electrolyte is an electrolyte salt dissolved in an electrolyte solvent, wherein
the solvent consists of at least 80% DMC (dimethyl carbonate) or AN (acetonitrile) or at least 80% mixtures of AN and DMC and
the electrolyte salt is stable in water and consists of one or more selected from Li-BETI (LiN (C ₂ F ₅ SO ₂ ) ₂ ), LiBF ₄ , LiClO ₄ or Li-PAF (LiPF ₃ (C ₂ F ₅ ) ₃ ) , 5. Rechargeable lithium cell with improved cycle stability and good high current behavior, consisting of an anode film with an active anode intercalation material, a cathode film with an active cathode intercalation material and an electrolyte, consisting of an electrolyte salt, dissolved in an electrolyte solvent, characterized in that
the active anode material is a lithium M-oxide, which has the spinel structure as the crystal structure, at least 90% of the metal M being transition metal and at least 75% of the metal M being titanium,
the active cathode intercalation material is one or more selected from
a lithium M-oxide which has the spinel structure, at least 90% of the metal M being transition metal and at least 75% of the transition metal being manganese,
a lithium transition metal phosphate which has the olivine structure or
a lithium M-oxide, which has a layer structure (R-3 m), at least 90% of the metal M being transition metal,
the electrolyte is an electrolyte salt dissolved in an electrolyte solvent
the solvent is DMC (dimethyl carbonate) or AN (acetonitrile) or mixtures of AN and DMC and
the electrolyte salt is stable in water and consists of one or more selected from Li-BETI (LiN (C ₂ F ₅ SO ₂ ) ₂ ), LiBF ₄ , LiClO ₄ or Li-PAF (LiPF ₃ (C ₂ F ₅ ) ₃ ) , 6. Rechargeable lithium cell with improved high-current behavior and improved cycle stability consisting of an anode film with an active anode intercalation material, a cathode film with an active cathode intercalation material and an electrolyte consisting of electrolyte salt, dissolved in an electrolyte solvent, characterized in that
the active anode material is a lithium M-oxide, which has the spinel structure as crystal structure, wherein at least 90% of the metal M is transition metal, at least 75% of the metal M is titanium and the BET surface of the lithium M-oxide is between 1 and 20 m ² / g,
the active cathode intercalation material is a lithium M-oxide which has the spinel structure, at least 90% of the metal M being manganese and the BET surface area of the lithium M-oxide being between 0.5 and 15 m ² / g and
the electrolyte is an electrolyte salt dissolved in an electrolyte solvent, wherein
the solvent consists of non-cyclic molecules and is at least 50% AN (acetonitrile) and
the electrolyte salt is stable in water. 7. Rechargeable lithium cell with improved high-current behavior and improved cycle stability consisting of an anode film with an active anode intercalation material, a cathode film with an active cathode intercalation material and an electrolyte consisting of an electrolyte salt, dissolved in an electrolyte solvent, characterized in that
the active anode material is a lithium M-oxide, which has the spinel structure as crystal structure, wherein at least 90% of the metal M is transition metal, at least 75% of the metal M is titanium and the BET surface of the lithium M-oxide is between 2 and 15 m ² / g,
the active cathode intercalation material is a lithium M-oxide which has the spinel structure, at least 90% of the metal M being manganese and the BET surface area of the lithium M-oxide being between 1 and 7 m ² / g and
the electrolyte is an electrolyte salt dissolved in an electrolyte solvent, wherein
the solvent consists of non-cyclic molecules and is at least 80% AN (acetonitrile) and
the electrolyte salt is stable in water. 8. Rechargeable lithium cell with improved high current behavior and improved cycle stability consisting of an anode film with an active anode intercalation material, a cathode film with an active cathode intercalation material and an electrolyte consisting of an electrolyte salt, dissolved in an electrolyte solvent, characterized in that
the active anode material is a lithium M-oxide, which has the spinel structure as the crystal structure, at least 90% of the metal M being transition metal and at least 75% of the metal M being titanium and the BET surface of the lithium M-oxide is between 2 and 10 m ² / g,
the active cathode intercalation material is a lithium M-oxide which has the spinel structure, at least 90% of the metal M being manganese and the BET surface area of the lithium M-oxide being between 1 and 6 m ² / g and
the electrolyte is an electrolyte salt dissolved in an electrolyte solvent, wherein
the solvent is AN (acetonitrile) and
the electrolyte salt is stable in water and consists of one or more selected from Li-BETI (LiN (C ₂ F ₅ SO ₂ ) ₂ ), LiBF ₄ or Li-PAF (LiPF ₃ (C ₂ F ₅ ) ₃ ). 9. Rechargeable lithium cell with improved cycle stability and good high-current behavior, consisting of an anode film with an active anode intercalation material, a cathode film with an active cathode intercalation material and an electrolyte consisting of an electrolyte salt, dissolved in an electrolyte solvent, characterized in that
the active anode material is a lithium M-oxide, which has the spinel structure as crystal structure, wherein at least 90% of the metal M is transition metal, at least 75% of the metal M is titanium and the BET surface of the lithium M-oxide is between 1 and 10 m ² / g,
the active cathode intercalation material has a BET surface area between 0.5 and 6 m ² / g and is one or more selected from
a lithium M-oxide with spinel structure, wherein at least 90% of the metal M is transition metal and at least 75% of the transition metal is manganese or
a lithium M-oxide, which has a layer structure (R-3 m), at least 90% of the metal M being transition metal and
the electrolyte is an electrolyte salt dissolved in an electrolyte solvent, wherein
the solvent consists of non-cyclic molecules and is at least 50% DMC (dimethyl carbonate) and
the electrolyte salt is stable in water. 10. Rechargeable lithium cell with improved cycle stability and good high-current behavior, consisting of an anode film with an active anode intercalation material, a cathode film with an active cathode intercalation material and an electrolyte consisting of an electrolyte salt, dissolved in an electrolyte solvent, characterized in that
the active anode material is a lithium M-oxide, which has the spinel structure as crystal structure, wherein at least 90% of the metal M is transition metal, at least 75% of the metal M is titanium and the BET surface of the lithium M-oxide is between 1 and 10 m ² / g,
the active cathode intercalation material has a BET surface area between 0.5 and 6 m ² / g and is one or more selected from
a lithium M-oxide with spinel structure, wherein at least 90% of the metal M is transition metal and at least 75% of the transition metal is manganese or
a lithium M-oxide, which has a layer structure (R-3 m), at least 90% of the metal M being transition metal and
the electrolyte is an electrolyte salt dissolved in an electrolyte solvent, wherein
the solvent consists of non-cyclic molecules and is at least 80% DMC (dimethyl carbonate) and
the electrolyte salt is stable in water. 11. Rechargeable lithium cell with improved cycle stability and good high-current behavior, consisting of an anode film with an active anode intercalation material, a cathode film with an active cathode intercalation material and an electrolyte consisting of an electrolyte salt, dissolved in an electrolyte solvent, characterized in that
the active anode material is a lithium M-oxide, which has the spinel structure as crystal structure, wherein at least 90% of the metal M is transition metal, at least 75% of the metal M is titanium and the BET surface of the lithium M-oxide is between 1 and 10 m ² / g,
the active cathode intercalation material has a BET surface area between 0.5 and 6 m ² / g and is one or more selected from
a lithium M-oxide with spinel structure, wherein at least 90% of the metal M is transition metal and at least 75% of the transition metal is manganese or
a lithium M-oxide, which has a layer structure (R-3 m), at least 90% of the metal M being transition metal and
the electrolyte is an electrolyte salt dissolved in an electrolyte solvent, wherein
the solvent is DMC (dimethyl carbonate) and
the electrolyte salt is stable in water and consists of one or more selected from Li-BETI (LiN (C ₂ F ₅ SO ₂ ) ₂ ), LiBF ₄ , LiClO ₄ or Li-PAF (LiPF ₃ (C ₂ F ₅ ) ₃ ) , 12. Rechargeable lithium cell with improved cycle stability and good high current behavior, consisting of an anode film with an active anode intercalation material, a cathode film with an active cathode intercalation material and an electrolyte, consisting of an electrolyte salt, dissolved in an electrolyte solvent, characterized in that
the active anode material is a lithium M-oxide, which has the spinel structure as crystal structure, wherein at least 90% of the metal M is transition metal, at least 75% of the metal M is titanium and the BET surface of the lithium M-oxide is between 0.5 and 10 m ² / g,
the active cathode intercalation material is a lithium M phosphate with olivine structure, at least 90% of M being transition metal and
the electrolyte is an electrolyte salt, dissolved in an electrolyte solvent, characterized in that
the solvent consists of non-cyclic molecules and
the electrolyte salt is stable in water. 13. Rechargeable lithium cell with improved cycle stability and good high-current behavior, consisting of an anode film with an active anode intercalation material, a cathode film with an active cathode intercalation material and an electrolyte, consisting of an electrolyte salt, dissolved in an electrolyte solvent, characterized in that
the active anode material is a lithium M-oxide, which has the spinel structure as crystal structure, wherein at least 90% of the metal M is transition metal, at least 75% of the metal M is titanium and the BET surface of the lithium M-oxide is between 0.5 and 10 m ² / g,
the active cathode intercalation material is a lithium M phosphate with olivine structure, at least 90% of M being transition metal and
the electrolyte is an electrolyte salt, dissolved in an electrolyte solvent, characterized in that
the solvent consists of non-cyclic molecules and consists of at least 80% MC (dimethyl carbonate) or AN (acetonitrile) or at least 80% mixtures of DMC and AN and
the electrolyte salt is stable in water and consists of one or more selected from Li-BETI (LiN (C ₂ F ₅ SO ₂ ) ₂ ), LiBF ₄ , LiClO ₄ or Li-PAF (LiPF ₃ (C ₂ F ₅ ) ₃ ) , 14. Rechargeable lithium cell with improved cycle stability and good high current behavior, consisting of an anode film with an active anode intercalation material, a cathode film with an active cathode intercalation material and an electrolyte consisting of electrolyte salt, dissolved in an electrolyte solvent, characterized in that
the active anode material is a lithium M-oxide, which has the spinel structure as a crystal structure, at least 90% of the metal M being transition metal and at least 75% of the metal M being titanium and the BET surface of the lithium M-oxide is between 0.5 and 6 m ² / g,
the active cathode intercalation material is a lithium M-phosphate with olivine structure, at least 90% of M being transition metal and
the electrolyte is an electrolyte salt, dissolved in an electrolyte solvent, characterized in that
the solvent is DMC (dimethyl carbonate) or AN (acetonitrile) or mixtures of DMC and AN and
the electrolyte salt is stable in water and consists of one or more selected from Li-BETI (LiN (C ₂ F ₅ O ₂ ) ₂ ), LiBF ₄ , LiClO ₄ or Li-PAF (LiPF ₃ (C ₂ F ₅ ) ₃ ) , 15. A lithium cell according to one of claims 6 to 8, characterized in that
the cathode film contains between 10 and 25 mg of active cathode material per cm ² ,
the volume packing density of the active cathode material in the cathode film is between 40-60%,
the anode film contains between 7 and 20 mg of active anode material per cm ² and
the volume packing density of the active anode material in the anode film is between 40-60%. 16. A lithium cell according to one of claims 9 to 11, characterized in that
the cathode film contains between 15 and 35 mg of active cathode material per cm ² ,
Volume packing density of the active cathode material in the cathode film is between 50-75%,
Anode film contains between 10 and 25 mg of active anode material per cm ² and
the volume packing density of the active anode material in the anode film is between 50-75%. 17. A lithium cell according to one of claims 1 to 16, characterized in that the ratio between cathode capacity and anode capacity between 0.7 and 0.95 is. 18. A rechargeable lithium battery characterized in that the battery at least contains a lithium cell according to any one of claims 1 to 17. 19. A lithium battery, characterized in that the battery has at least one Contains lithium cell according to one of claims 6 to 8 or 15, wherein the battery can be charged in the discharged state for more than 1 minute at 30C rate and in charged state can be discharged at least 30 seconds at 60C rate without that the voltage deviates more than 20% from the OCV voltage. 20. A lithium battery, characterized in that the battery has at least one Contains lithium cell according to one of claims 9 to 11 or 16, wherein the battery can be charged at 6C rate in the discharged state for more than 5 minutes and in charged state can be discharged at 10C rate at least 3 minutes without the Voltage deviates more than 20% from the OCV voltage. 21. A rechargeable lithium battery that has at least two lithium cells accordingly contains one of claims 1 to 16 or 17, wherein the battery characterized is that at least one bipolar plate consisting of anode film, aluminum substrates and cathode film is used, the aluminum substrate being an aluminum plate or aluminum foil and the anode film and the cathode film are congruent opposite sides of the aluminum substrate. 22. A rechargeable lithium battery according to claim 21, which has at least three This contains lithium cells and a stack of at least two bipolar plates characterized in that the bipolar plates, separated by an electrolyte, in series are switched. 23. A large rechargeable lithium battery according to claim 22, which contains at least 6 lithium cells and a stack of at least 5 bipolar plates, characterized in that
at least 5 and at most 100 bipolar plates, separated from an electrolyte, are connected in series and
the cathode film on the bipolar plates each has an extent between 100 and 4000 cm ² .