Lithium battery and solar cell integrated design - Power Circuit - Circuit Diagram

The solidification trend of lithium ion rechargeable batteries and lithium polymer rechargeable batteries is increasing. Among them, some manufacturers have begun to sell products. After solidification, it is expected to open up new uses due to its unprecedented characteristics.

An all solid lithium ion or polymer rechargeable battery uses a solid material as the electrolyte of the battery. Since the electrolyte is not used at all, liquid leakage does not occur, and the possibility of fire and explosion is greatly reduced. In addition, most products also have a film thickness of only μ ~ 100μm (excluding the bottom plate), light weight and the bottom plate can be bent. However, there are also problems of low power density and narrow operating temperature range.

These issues have recently been greatly improved, and a number of technologies have entered the practical stage. For example, South Korea's GS Caltex has produced ultra-thin, postage-sized lithium-ion rechargeable batteries, and has begun sampling in Japan and other places. Although the capacity itself is only 0.5 mAh, the volumetric energy density exceeds 800 Wh/L, which is more than 20% higher than that of a conventional lithium ion rechargeable battery. The charging rate is high, up to 50C.

The key is experience and know-how

GS Caltex's battery manufacturing equipment and manufacturing experience are provided by ULVAC. "Affordable" is an ordinary sputtering manufacturing device that can produce an electrolyte layer in addition to positive and negative electrodes. It is also expected to greatly expand the area. However, such a battery can not be manufactured by anyone. "Manufacturing experience and know-how such as temperature management during high-temperature processing is the key to performance improvement."

GEOMATEC and Iwate University have also developed all-solid-state lithium-ion rechargeable batteries that use sputtering to achieve positive and negative electrodes and electrolyte layers. But the features are different from the GS Caltex battery. For example, "a resin film can be used for the bottom plate without the need for a high temperature process." However, the capacity is only about 0.1mAh. The reason is that "the anode does not use lithium, so the terminal voltage is low".

Expected for large area devices

The above two development cases use semiconductor manufacturing technology. The Idemitsu Kosan and the Mie Prefecture Industrial Support Center have chosen a manufacturing process different from that of semiconductors, and strive to reduce costs significantly. However, both technology camps need to make greater efforts in practical use.

A few years ago, Izumi was developing an all-solid-state lithium-ion rechargeable battery for powdered "sulfide lithium salt" (Iwate). There are two main recent developments: 1 size has increased from the size of the business card to the size of A6, 2 saves the previous kgf/cm2 pressure required for the previous output power. However, there is still a problem of flexibility and electrolyte uniformity, and it is necessary to further improve the manufacturing process.