EnerDel Thin-Prismatic Cell for HEV's

EnerDel has developed a unique lithium ion technology that offers a number of advantages that are derived from the chemistry, mechanical design and the opportunities it offers in the manufacturing process. 

• Chemistry Advantage
  • Long life
  • Safety
  • Low heat generation
  • Good cycle performance
• Mechanical Design Advantage
  • Best design for high power
  • Equal distribution of pressure on electrode for a long life
  • Good heat dissipation for safety, long life, and cost impact
  • Mechanical strength
  • Easy battery connections for pack manufacturing
• Manufacturing Process
  • Fully automated
  • High material utilization

One of unique features of EnerDel is that we develop the cell mechanical and chemistry design starting from the battery system requirements. Traditional battery companies try to make a battery pack after they optimize the chemistry and mechanical components in a traditional metal case at the cell level. The result is that even if you have the best cell design, it is not always the best design for battery packs which is the final product the customer cares about. As a consequence the cost, weight, volume, safety, etc. can be affected in a negative manner. At EnerDel, talented and experienced lithium ion engineers and automobile electronics and mechanical designers are working closely together as one team, and the cell and battery system development is going on simultaneously.

EnerDel believes longevity, safety and cost are the most important elements demanded by the automotive customers. To achieve these key attributes, EnerDel is convinced that a non-graphite anode material is key for success in automobile battery business. Almost all lithium ion batteries in the market, including for notebook computers, mobile phones, power tools, EVs, etc. are using a graphite anode. The advantage of the graphite anode is that it has a stable and high capacity, but needs to create a strong SEI layer in order to provide this advantage.  However, when you construct a large battery pack, EnerDel believes one can not ignore the potential heat generation from the decomposition of SEI layer under certain conditions in large battery systems, and this can have a significant effect on the safety of the battery.  (Regarding further explanation and impact of the  SEI layer please refer to the  FAQ page , as well as the Safety section under the Advantages page). EnerDel believes that just stabilizing the cathode material would not offer enough safety levels for automobile applications.

EnerDel has developed our own Lithium Titanate Anode material in collaboration with Argonne National Laboratory (ANL) for HEV applications. We have also developed a Hard Carbon anode lithium ion battery for PHEV/EV applications. Both chemistries show extremely good safety and cycle life performance in comparison with graphite based lithium ion batteries. (Please also refer to the Product page of our web site).

2. Mechanical Design Advantages

The mechanical design inside the EnerDel cell is a stack design where the electrodes are stacked on top of each other, i.e. multiple anode and cathode pairs of electrodes are stacked on top of each other. This differs markedly from almost all lithium ion batteries in the market today, including batteries for notebook computers, mobile phones, power tools, etc., which are using a wound design, i.e. where one anode and one cathode electrode of the same lengths are wound up. EnerDel believes the wound design works well for smaller , high energy cells that are employed in portable electronic products, but is not advantageous for larger, high rate and high power cells.  The main advantage for the wound method is reduction of cost by achieving high through put from high speed process. But, as the size of the cell and the power requirements escalate the disadvantages of the wound design become apparent as numerous tabs have to be attached to the electrodes to be able to draw the high currents out of the battery and the increasing length of the electrodes entails that the high speed process has to slow down significantly if it is to e able to keep the same level of accuracy in the winding process . In contrast, the EnerDel stack design gains a number of performance advantages both at the cell level and in the system level design as mentioned below in the Technology Comparison.

3. Manufacturing Process Advantage

EnerDel’s stack design in the cell is accomplished with a fully automated mass production process. The design also translates into greater flexibility in the designing of the battery system (mechanical design and layout of the battery pack), as well as providing for an easier assembly and mass manufacturing process of the battery pack. A further advantage is that the raw material yield is extremely good as a result of the stack design. These advantages all offer a cost competitive advantage in the manufacturing process of cell and system.

Technology Comparison

The table below provides a comparison between competitive lithium-ion chemistries in cylindrical cell design and EnerDel's lithium ion flat stack prismatic cell design, and the advantages our technology offers.