2 Pack 3.7V 600mAh Li-ion Rechargeable Battery for K9 Robot Dog - USB

In this review of the 2 Pack 3.7V 600mAh Li-ion Rechargeable Battery for the K9 robot dog, the bottom line is simple: this kit is for owners who need a direct, reliable replacement battery pair with added safety during charging. The package includes two slim 3.7V batteries and two USB charge cables, and the biggest reason to buy is the combination of correct physical fit for the K9 and built-in protections on the USB cable that reduce risk while topping up cells. This review focuses on day-to-day use, charging behavior, and whether the set is a practical spare for toy owners.

Key Features

• Exact fit and compact size: The 34 x 50 x 5mm profile makes these cells easy to slot into the K9 robot dog battery compartment without modification.
• Reasonable capacity: The 600mAh capacity provides a useful run time for play sessions and is balanced for small toy motors and electronics.
• Standard 1S voltage: At 3.7V (1S), the voltage matches what the K9 requires so no voltage conversion is needed.
• Included USB charge cables: Each battery comes with a USB charger cable that offers short circuit, overload and overvoltage protection for safer charging from USB ports.
• Lightweight spare set: At about 20 grams per battery, they do not noticeably change the toy's balance or handling when fitted.

Who It's For

This kit is best for owners of the K9 remote control robot dog who want an immediate replacement or a spare pair for extended play. Hobbyists who need a direct swap with minimal fuss will appreciate the plugs and the compact 34 x 50 x 5mm size that fits the intended compartment.

Those who operate larger RC vehicles, need higher capacity cells, or require rapid high-current discharge for powerful motors should look elsewhere, since these 600mAh 1S Li-ion cells are optimized for small toy electronics rather than high-drain applications.

Pros & Cons

Pros

• Good physical compatibility with the K9 robot dog for a hassle-free replacement.
• USB charger cables include short circuit, overload and overvoltage protection for safer charging from common USB ports.
• Lightweight construction keeps the toy balanced and maintains normal handling.
• Includes two batteries and two cables so you have a ready spare for back-to-back play.

Cons

• 600mAh capacity is modest, so runtime is limited compared with larger hobby batteries.
• Not intended for high-drain RC use beyond small toy robots.

Specifications

Brand	Itexkun
Voltage	3.7V (1S)
Capacity	600mAh
Dimensions	34 x 50 x 5mm
Weight	20 gram (each)
Plug Type	SM-2P plug
Package Contents	2 x Battery, 2 x USB Charger

Our Verdict

This 2 pack is a sensible, low-friction replacement for K9 robot dog owners who want matching spare batteries and safer USB charging. The physical dimensions and SM-2P plug ensure a direct fit, and the cable protections make topping up convenient. It is good value for toy users who prioritize compatibility and simple safe charging over long runtime or high-discharge performance.

Frequently Asked Questions

Will these batteries fit my K9 robot dog?
Yes. The batteries are sized 34 x 50 x 5mm with an SM-2P plug, which matches the K9 robot dog battery compartment and connector.

Can I charge the batteries with a standard USB port?
Yes. Each battery includes a USB charge cable with short circuit, overload and overvoltage protection for safer charging from standard USB power sources.

Are these suitable for high-power RC vehicles?
No. These 600mAh 3.7V cells are intended for small toys like the K9 robot dog and are not designed for high-drain larger RC vehicles.