DESCARTES - DEFI SUR LE STOCKAGE ELECTROCHIMIQUE ASSOCIE A DES ROBOTS TELECOMMANDES

LIght roBOt Battery – LIBOB

LIBOB LIght roBOt Battery

High Energy Li-ion accumulators (ca. 300Wh/kg) integrating novel chemistries (Li rich/Si-C) in respect with REACH requirements and with care for safety concerns

Development of high energy lithium cells for terrestrial mobile robots applications

Li-ion technology integrating new active materials at both negative and positive electrodes <br />Targeting 300Wh/kg or above 700Wh/L at cell level <br />Cobalt-free materials in agreement with REACH requirements <br />12 to 20V Battery pack with BMS for a continuous discharge at 8A and current peak of 16A <br />At least 30% increase in autonomy <br />In synergy with other developments in the energy sector <br />

managed
- Li-rich lamellar oxides are promising candidates however their conductivity at low temperatures may have to be boosted by compositions adjustments. Time allocated to the proof of concept would not be sufficient for such development. It could be a second stage improvement (back up solution envisaged)
-Energy versus Power Optimized Design induces lower reachable specific energy than pure Energy Design. However the specific energy will remain anyway higher than with conventional chemistry
- Cycling and storage life of Li-rich material is also a challenge. First, relatively high charge voltage of the positive electrode can decrease stability of the material / electrolyte interface
-Electrolyte formulation may also have to be optimized in link with the silicon-based negative electrode
-Fifty to One hundred of cycles are targeted in a preliminary stage with this very high energy technology
-Corresponding module requested electrical & mechanical optimization, BMS interface

First year confirms hypothesis to reach 300Wh/kg cell level with 4.5Ah capacity pouch
Materials study validates Li-rich with silicon composite (SiC 60/40) as promising candidate , and formulations tests allowed to optimize electrodes process
Prototypes performances confirm our performances assumptions

Next work deals with cells conception adjustment to fit with waited robot battery pack specifications
At least 30% increase in autonomy
In synergy with other developments in the energy sector

To come

The present activity will be dedicated to the development of high energy lithium cells for terrestrial mobile robots applications. Among various parameters, high specific energy density (massic and volumic) is the most important criteria for embedded power sources. To succeed, very promising Li-ion technology integrating new active materials at both negative and positive electrodes in replacement of the conventional cells based on Lithium Cobalt Oxide/Graphite technologies is proposed, targeting 300Wh/kg or above 700Wh/L at cell level. These materials are cobalt-free in agreement with REACH requirements. A rechargeable battery pack, including cell to cell connections, packaging and Battery Management System (BMS) will be specifically designed and optimized to integrate such innovative technology in order to reach voltages between 12 and 20V, for a continuous discharge at 8A and current peak of 16A. This technology will be designed so that the product demonstrating at least 30% increase in autonomy compared to the most competitive current technologies with acceptable number of charges/discharges and withstanding a test plan built from Qualification Tests as described through the relevant reference. The selected energy technology is one under development for other terrestrial applications like electric aircrafts or vehicles and also under space program for satellites to allow military application to benefit from those synergies with other developments in the energy sector.

Project coordinator

Madame Florence FUSALBA (Commissariat à l'Energie Atomique et aux Energies Alternatives)

The author of this summary is the project coordinator, who is responsible for the content of this summary. The ANR declines any responsibility as for its contents.

Partner

CEA/LITEN Commissariat à l'Energie Atomique et aux Energies Alternatives
AGLO DEVELOPPEMENT

Help of the ANR 409,080 euros
Beginning and duration of the scientific project: - 36 Months

Useful links