{"id":1596,"date":"2026-07-28T10:08:11","date_gmt":"2026-07-28T02:08:11","guid":{"rendered":"https:\/\/www.kbtbattery.com\/?post_type=product&p=1596"},"modified":"2026-07-28T10:08:14","modified_gmt":"2026-07-28T02:08:14","slug":"3-7v-4000mah-li-ion-21700-battery-with-button-top-protection-pcb","status":"publish","type":"product","link":"https:\/\/www.kbtbattery.com\/zh\/product\/3-7v-4000mah-li-ion-21700-battery-with-button-top-protection-pcb\/","title":{"rendered":"3.7V 4000mAh Li-ion 21700 Battery with Button Top Protection PCB"},"content":{"rendered":"
\n
\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n
Item<\/th>\nKBT21700-4000-PCB<\/th>\n<\/tr>\n<\/thead>\n
Manufacturer<\/td>\nKBT BATTERY<\/td>\n<\/tr>\n
Chemistry<\/td>\nLithium-ion<\/td>\n<\/tr>\n
Size<\/td>\n21700<\/td>\n<\/tr>\n
Diameter<\/td>\n21mm<\/td>\n<\/tr>\n
Length<\/td>\n76mm<\/td>\n<\/tr>\n
Positive Terminal<\/td>\nButton Top<\/td>\n<\/tr>\n
Capacity<\/td>\n4000mAh<\/td>\n<\/tr>\n
Continuous Discharge Rating (max)<\/td>\n3C<\/td>\n<\/tr>\n
Nominal Voltage<\/td>\n3.7V<\/td>\n<\/tr>\n
Maximum Voltage<\/td>\n4.2V<\/td>\n<\/tr>\n
Discharge Cut-off Voltage<\/td>\n2.5V<\/td>\n<\/tr>\n
Protected<\/td>\nYes<\/td>\n<\/tr>\n
Protection Functions<\/td>\nShort Circuit Protection, Overcharge Protection, Discharge Protection<\/td>\n<\/tr>\n
Rechargeable<\/td>\nYes<\/td>\n<\/tr>\n
Rechargeable Cycles<\/td>\n800<\/td>\n<\/tr>\n
Approx. Weight<\/td>\n72g<\/td>\n<\/tr>\n<\/tbody>\n<\/table>\n<\/div>\n<\/section>","protected":false},"excerpt":{"rendered":"
<\/div>\n\n\n\n\n\n
\n
\n
Lithium-ion<\/div>\n<\/div>\n<\/td>\n<\/tr>\n
\n
\n
3.7V<\/div>\n<\/div>\n<\/td>\n<\/tr>\n
\n
\n
4000mAh<\/div>\n<\/div>\n<\/td>\n<\/tr>\n<\/tbody>\n<\/table>\n
\n

Protected 21700 lithium-ion cells for rechargeable-battery applications. Standard-model sourcing and OEM\/ODM available.<\/p>\n

Customization Options<\/b><\/p>\n

    \n
  • Protection PCB<\/li>\n
  • Terminal configuration and packing method<\/li>\n<\/ul>\n

    Key Features<\/b><\/p>\n

      \n
    • 3.7V nominal voltage and 4000mAh capacity<\/li>\n
    • 21700 format with Button Top positive terminal<\/li>\n
    • Built-in protection plate with short circuit, overcharge, and discharge protection<\/li>\n
    • 3C maximum continuous discharge rating<\/li>\n
    • 800 rechargeable cycles stated in the source gallery<\/li>\n<\/ul>\n<\/div>","protected":false},"featured_media":1601,"template":"","meta":{"themepark_post_bcolor":"#f5f5f5","themepark_post_width":"1022px","themepark_post_img":"","themepark_post_img_po":"left","themepark_post_img_re":false,"themepark_post_img_cover":false,"themepark_post_img_fixed":false,"themepark_post_hide_title":false,"themepark_post_main_b":"","themepark_post_main_p":100,"themepark_paddingblock":false,"_geo_short_summary":"","_geo_structured_desc":"","_geo_faqs":"","_geo_key_points":"","_geo_target_audience":"","_geo_content_type":"","_geo_last_modified":"","_geo_version":0,"themepark_seo_title":"","themepark_seo_description":""},"product_brand":[],"product_cat":[155],"product_tag":[195,197,198,179,196],"class_list":["post-1596","product","type-product","status-publish","has-post-thumbnail","product_cat-155","product_tag-21700-battery","product_tag-3-7v-lithium-ion-battery","product_tag-4000mah-rechargeable-cell","product_tag-oem-battery-sourcing","product_tag-protected-button-top-battery","pa_capacity-20015000mah","pa_chemistry-lithium-ion","pa_voltage-3-7v","first","instock","shipping-taxable","product-type-simple"],"yoast_head":"\n21700 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