1. The judgment of the court of first instance is modified as follows.

The defendant delivered by the defendant from the plaintiff 9.

1. Basic facts

A. On May 24, 2016, the Plaintiff entered into a product supply contract (hereinafter “instant supply contract”) with the content that the Defendant would be supplied with KRW 10,000 with 79,750,000,00 (hereinafter “instant auxiliary ship”) from the Defendant.

B. Since then, the Plaintiff paid all the price for the goods under the instant supply contract to the Defendant, and the Defendant also supplied the Plaintiff with all the instant supplementary distribution.

C. On the other hand, the Plaintiff, while selling part of the instant supplementary sheet supplied by the Defendant to ordinary consumers or providing intra-company samples, etc., was kept in storage without selling 9,110 currently.

On September 1, 2016, the Plaintiff sent to the Defendant a content-certified mail containing a declaration of intent to cancel the instant supply contract on the grounds of the defect, etc. of the auxiliary distribution, and around that time, the said content-certified certificate reaches the Defendant.

E. As a result of the appraisal of the fixed capacity of the instant auxiliary ship, the fixed capacity was measured at 7,576-7,662mAh.

[Ground of Recognition] Facts without dispute, Gap evidence Nos. 1, 3, 10, 11 (including branch numbers, if any; hereinafter the same shall apply), the result of entrustment to the President of the Korea Testing and Research Institute for Construction and Living Environment (Appraiser A), a foundation of the first instance court for appraisal (hereinafter "the result of appraisal of this case"), the purport of the whole pleadings

2. The plaintiff's assertion

A. In the first place, although the Defendant had a contractual obligation to supply the Plaintiff with any defect pursuant to the instant supply contract, the Defendant supplied the Plaintiff with the instant assistant distribution to which the Plaintiff had a contractual obligation to supply the auxiliary distribution without any defect, ① the Plaintiff, ② the shortage of capacity, ② the defect where the interior structure is easily pushed down due to the low compressing load, ③ the product conspiracy part, and ③ the defect where the safety problem is at issue due to the kylro, which constitutes a serious defect that could not achieve the purpose of the instant supply contract.

The plaintiff is due to the defendant's incomplete performance.