方法一：调用KE时配置好参数就行，代码如下：

<link rel="stylesheet" href="kindeditor/themes/default/default.css" />
<script charset="utf-8" src="kindeditor/kindeditor-all.js"></script>
<script charset="utf-8" src="kindeditor/lang/zh-CN.js"></script>
<script>
var KE;
KindEditor.ready(function(K) {
    KE = K.create('#content',{
    imageSizeLimit : '10MB', //批量上传图片单张最大容量
    imageUploadLimit : 100 //批量上传图片同时上传最多个数
    });
});
</script>
<textarea id="content" name="content" style=" width: 99%; height: 500px; visibility: hidden; display: block; "></textarea>

imgPath = self.pluginsPath + 'multiimage/images/', //默认上传目录
imageSizeLimit = K.undef(self.imageSizeLimit, '1MB'), //默认上传单个文件大小
imageFileTypes = K.undef(self.imageFileTypes, '*.jpg;*.gif;*.png'), //默认上传类型
imageUploadLimit = K.undef(self.imageUploadLimit, 20), //默认一次性批量上传图片的个数

方法三：貌似直接修改\kindeditor\php\upload_json.php 29行，也管用

//最大文件大小
$max_size = 8000000;