JP2001283903A5 - - Google Patents

Description

（但し、Ｒ1及びＲ2は、水素原子、炭素数１〜４のアルキル基、又はフェニル基、又は炭素数１〜４のアルキル基を有するフェニル基を示す。） [Claims]
1. The non-aqueous electrolyte solution comprises a positive electrode having a substance that occludes / releases lithium ions, a negative electrode having a substance that occludes / releases lithium ions or metallic lithium or a lithium alloy, and a non-aqueous electrolyte solution. Is a non-aqueous electrolyte secondary battery, which contains the compound shown in Chemical formula 1, trimethyl phosphate, and fluorinated ether.
[Chemical 1]

(However, R1 and R2 indicate a hydrogen atom, an alkyl group having 1 to 4 carbon atoms, or a phenyl group, or a phenyl group having an alkyl group having 1 to 4 carbon atoms.)

（但し、Ｒ1及びＲ2は、水素原子、炭素数１〜４のアルキル基、又はフェニル基、又は炭素数１〜４のアルキル基を有するフェニル基を示す。） 0004
[Means for solving problems]
The non-aqueous electrolyte secondary battery according to the present invention has been made in view of the above problems, and has a positive electrode having a substance that occludes and releases tium ions, and a substance that occludes and releases lithium ions, or a metallic lithium or lithium alloy. The non-aqueous electrolyte solution includes a negative electrode and a non-aqueous electrolyte solution, and the non-aqueous electrolyte solution contains a compound represented by Chemical formula 3 (= Chemical formula 1), trimethyl phosphate (hereinafter TMP), and fluorinated ether (HCF ₂ CF ₂ CH ₂ OCF). ₂ CF ₂ H: hereinafter HFE) is contained. Further, the compound content represented by Chemical formula 3 is preferably 1 to 50 vol%.
[Chemical 3]

(However, R1 and R2 indicate a hydrogen atom, an alkyl group having 1 to 4 carbon atoms, or a phenyl group, or a phenyl group having an alkyl group having 1 to 4 carbon atoms.)

0005
BEST MODE FOR CARRYING OUT THE INVENTION
The present invention comprises a positive electrode having a substance that occludes and releases lithium ions as a constituent element, a negative electrode having a substance that occludes and releases lithium ions as a component, and a non-aqueous electrolytic solution. It is characterized by containing the compound represented by Chemical formula 3 and trimethyl phosphate or fluorinated ether. In particular, it preferably contains 1 to 50 vol% of the compound represented by Chemical formula 3, trimethyl phosphate and fluorinated ether. This makes it possible to provide a water electrolyte secondary battery having improved battery safety during abnormal heat generation. The components of the battery other than the above can be appropriately configured without any particular restrictions, and examples thereof are as follows.

[Example 4] Comparative Example in which 1 mol / liter _{of LiPF 6} was dissolved in a mixed solution of the compound shown in Chemical formula 4, dimethyl carbonate, TMP, and HFE in a mixed ratio (volume ratio) of 60:20:10:10. The electrolytic solution of 1 was used.

[Comparative Example 1] A solution prepared by dissolving 1 mol / liter _{of LiPF 6 in} a mixed solution of dimethyl carbonate, TMP and HFE at a mixing ratio (volume ratio) of 20:40:40 was used as the electrolytic solution of Comparative Example 1.

[Comparative Example 2] _{1 mol / liter of LiPF 6} was dissolved in a mixed solution of ethylene carbonate, TMP and HFE at a mixing ratio (volume ratio) of 20:40:40, and this was used as the electrolytic solution of Comparative Example 2.

Those of LiPF ₆ was dissolved 1 mol / liter in a mixed solution of Comparative Example 3 compound and the mixing ratio of dimethyl carbonate represented by 4 (volume ratio) 20:80 was Comparative Example 3. Using the batteries of Examples 1 to 3 and Comparative Examples 1 to 4 described above, a constant current constant voltage charge of 4.2 V was performed at a current of 25 ° C. × 1 C for 3 hours, and then a discharge end voltage was charged at a constant current of 1 C. The discharge capacity was measured by discharging to 75 V. Further, using the batteries of Examples 1 to 3 and Comparative Examples 1 and 4, the constant current constant voltage charge of 4.31 V at 25 ° C. × 1C current was performed for 3 hours, and then the batteries were put into an oven at 150 ° C. The appearance was observed. The results are shown in Table 1.

EC is ethylene carbonate, DMC is dimethyl carbonate, TMP is trimethyl phosphate, and HFE is fluorinated ether. Examples 1 to 4 in which ethylene sulfite was added to the mixed solvent of TMP and HFE were capable of charging and discharging, whereas Comparative Examples 1 and 2 in which ethylene sulfate was not added could not be charged and discharged.

Further, in the batteries of Example 1 and Comparative Example 3 that could be charged and discharged, the electrolytic solution containing TMP and HFE did not cause any abnormality such as smoke in the battery during the oven test, and it is safe to use the nonflammable electrolytic solution. Was found to improve.

[0029]
【Effect of the invention】
The non-aqueous electrolyte secondary battery of the present invention has a positive electrode having a substance that stores and releases lithium ions as a component, a negative electrode that has a substance that stores and releases lithium ions or a metallic lithium or a lithium alloy as a component, and the above-mentioned non-aqueous electrolyte secondary battery. and a water electrolyte, the nonaqueous electrolyte solution, at least, which is characterized by using the mixture of compound and phosphoric acid trimethyl and fluorinated ether represented by Formula 3, thereby abnormal heat generation of batteries It is possible to provide a non-aqueous electrolyte secondary battery having improved battery safety in the above.