SPuttering appliqué aux accumulateurs au LIThium – SPLIT

SPLIT project aims to demonstrate that a technical breakthrough is possible for the improvement of the specific capacity of Li-ion batteries. The first objective is to demonstrate the feasibility of a Lithium-ion battery with a specific energy (by weight or volume) improved by 50 % thanks to the use of new families of negative and positive materials obtained by sputtering and/or PECVD process. The second objective is to validate the sputtering process in replacement of the present manufacturing process for the pasting of negative electrode. The present one is out of its range of use for the thinner electrodes requested by the new material. The use of sputtering process for this industrial purpose is new. This improvement relies on 2 relatively independent achievements : -- one negative electrode at industrial scale, based on silicon, which provides 1400 mAh/g with an average voltage of 0.3 V versus metallic lithium, obtained by sputtering and/or PECVD so as to manufacture simultaneously structured material and electrode ready for battery assembly after size adjustment. -- one positive material at laboratory scale, based on a lithiated transition metal fluoride and an electronic conductive network, sputtered in relatively thin nano-structured layer and performing by conversion reaction at more than 900 Wh/kg ; for example 300 mAh/g with 3.0 V of average voltage. The introduction of new industrial negative electrode is possible alone with at stake a significant gain of 20% in specific energy at battery level. A technico-economic evaluation of an industrial negative is included in the project. SPLIT is spread in three tasks. The task 0 deals with coordination. The task 1 deals with the new silicon based negative electrode and tests in complete cells, which include results of task 2. Eventually, the task 2 deals with the new material for positive electrode. For the tasks 1 and 2, SPLIT involves manufacturing, physico-chemical and electrochemical characterizations and understanding of several varieties of materials so as to select one couple which performs at the requested performances. The communication and the exploitation are defined in the project. SPLIT improves the competitive position of battery and sputtering French industries especially in front of Asian and American ones. It should allow development of these activities in France and also progress in understanding and manufacturing new materials and new principles of reactions which are necessary for the implementation of a breakthrough generation of batteries. The present generation incorporates metal oxides and graphite and has been optimized by incremental action for near 20 years. Targeted markets include professional portable electronics (communication, medical, video), individual or mass transportation by air or earth and renewable energy storage (especially for decentralized photovoltaic systems). The accessibility of the different markets depends on initial performances, duration and achievable cost. SPLIT is in full accordance with the background and the objective of MatetPro-2009 project call : "Functional Materials and Innovative Process". It will gather for 3 years scientific actors ICMCB and IPREM and industrial actors Saft and HEF which have extended knowledge in the fields of herein considered process and materials. It addresses the field of sustainable development by alloying extended use of electrical energy which is recognized for its flexibility and its compatibility with renewable modes of production. At term, storage is an essential complement for the development of photovoltaic and wind electricity production. SPLIT answers directly to one part of thematic axis 1 : Functionalities and associated Materials in title " materials for energy storage or transportation" and subtitle "electrodes for rechargeable batteries". In addition to the thematic axis 1, some aspects of thematic axis 3 : nano-structured materials, organic-inorganic hybrid materials, and also, thematic axis 4 : modelling and numeric simulations, multi-scale approaches, behaviour forecast, are addressed by SPLIT.