---
product_id: 628798982
title: "3.7V 503040 620mAh Rechargeable Lithium Polymer Battery, Suitable for cozmo Vector robot Battery replacement,SkyBell HD WiFi Video Doorbell、Flysight FPV Watch、 wireless speaker Battery replacement"
brand: "hxjnldc"
price: "€ 33.07"
currency: EUR
in_stock: true
reviews_count: 5
category: "Hxjnldc"
url: https://www.desertcart.gr/products/628798982-3-7v-503040-620mah-rechargeable-lithium-polymer-battery-suitable-cozmo
store_origin: GR
region: Greece
---

# 3.7V nominal, 4.2V max charge voltage 620mAh high-capacity power Built-in overcharge & short circuit protection 3.7V 503040 620mAh Rechargeable Lithium Polymer Battery, Suitable for cozmo Vector robot Battery replacement,SkyBell HD WiFi Video Doorbell、Flysight FPV Watch、 wireless speaker Battery replacement

**Brand:** hxjnldc
**Price:** € 33.07
**Availability:** ✅ In Stock

## Summary

> 🔋 Power up your tech game—never miss a beat with this sleek, smart battery!

## Quick Answers

- **What is this?** 3.7V 503040 620mAh Rechargeable Lithium Polymer Battery, Suitable for cozmo Vector robot Battery replacement,SkyBell HD WiFi Video Doorbell、Flysight FPV Watch、 wireless speaker Battery replacement by hxjnldc
- **How much does it cost?** € 33.07 with free shipping
- **Is it available?** Yes, in stock and ready to ship
- **Where can I buy it?** [www.desertcart.gr](https://www.desertcart.gr/products/628798982-3-7v-503040-620mah-rechargeable-lithium-polymer-battery-suitable-cozmo)

## Best For

- hxjnldc enthusiasts

## Why This Product

- Trusted hxjnldc brand quality
- Free international shipping included
- Worldwide delivery with tracking
- 15-day hassle-free returns

## Key Features

- • **Compact Yet Mighty:** Slim 41×30×5mm size fits discreetly into your favorite gadgets without bulk.
- • **Safe & Smart Battery Tech:** Japanese Seiko IC safeguards against overcharge, overcurrent, and short circuits for peace of mind.
- • **Lightweight & Long-Lasting:** At just 13g, enjoy extended device runtime without weighing down your tech.
- • **Power Your Smart Devices Seamlessly:** 620mAh capacity fuels your Cozmo, SkyBell, FPV watch & more with reliable energy.
- • **DIY Friendly with Plug & Play Flexibility:** Includes JST connector & heat-shrink sleeve for easy soldering or direct replacement—perfect for tinkerers.

## Overview

This 3.7V 620mAh rechargeable lithium polymer battery is engineered for seamless replacement in COZMO Vector robots, SkyBell HD WiFi doorbells, Flysight FPV watches, and wireless speakers. Featuring a compact 41×30×5mm form factor and weighing only 13g, it delivers reliable power with built-in Japanese Seiko IC protection against overcharge, overcurrent, and short circuits. Designed for DIY enthusiasts, it includes a JST 2-wire connector and heat-shrink sleeve for easy installation. Ideal for 3.7-5V devices under 2.294Wh, this battery ensures your smart gadgets stay energized and ready.

## Description

Product description DC 3.7V Model Table of Square Rechargeable Polymer Lithium Battery (applicable to 3.7V-5V electronic products) Please note that connector specifications and polarity are based on the product display image ,the red wire is the positive "+" and the black wire is the negative "-"The yellow (white) lead is a 'thermistor'，Do not reverse-charge or reverse-connectreverse. 3 -wire batteries retain red and black wires, which can replace 2 -wire batteries. Some products' original batteries may lack plugs, have incompatible plugs, or exhibit mismatched polarity. No worries—you can simply cut the wires and use the included heat-shrink tubing to connect the wires of the same color from the old plug. Package: 620mAh LiPo battery x 1 heat shrinkable insulating sleeve x 1 Compatible ： COZMO Vector robot、 SkyBell HD WiFi Video Doorbell、Flysight FPV Watch、 wireless speaker It can also be used for MP3, MP4, MP5, GPS, smart watches, power packs, detectors, More Other 3.7~5V electronic products with power less than 2.29Wh (620mAh). Size: 1.596×1.181×0.196inch (L*W*T) Size: 41×30×5mm (L*W*T) voltage: 3.7V Capacity: 620mAh Weight: 0.458oz（13g) Maximum current: 1A

Review: Cumple lo que promete - Una batería pequeña apta para los robots de Anki Cozmo y Vector. En mi caso fue para un Cozmo al que la batería que venía de fábrica no aguantaba ya la carga y era necesario reemplazarla. La batería viene con un conector JST típico en baterías y un pequeño trozo de tubo termorretráctil (que no utilicé). Buena calidad y mayor capacidad que la batería que venía de fábrica con Cozmo. Eso sí, si os aventuráis a desmontar a Cozmo, tened en cuenta que, aunque es relativamente sencillo, hay que hacerlo con cuidado, y la batería tiene que ser soldada a la placa. En cualquier caso, la batería de momento cumple bastante bien y aún no he tenido que cargarla desde que se la coloqué al robot.
Review: Works Great in Cozmo - Works great in Cozmo toys. Perfect fit. Installation isn't too hard but does require some time and patience. See the picture here of my son's Cozmo torn down to the point where the battery can be replaced. It looks like a lot of pieces but everything disassembles easily and goes back together pretty easy too. The head is a little tricky as there is a small spring that you have to fight as you put it together, but isn't too hard once you figure it out. Sort of like a puzzle. There is a video on YouTube by John that is super helpful. Just watch that once and you'll have it figured out. The hardest part for most people will be just soldering the wires to the circuit board. This battery comes with a JST plug, but you have to cut that off, strip the wires, and then solder them to the board. It's pretty trivial if you know how to solder, but could trip up people who've never used a soldering iron. You'll need to cut the red wire shorter and leave the black wire longer, since the leads come out the same side of the battery, so it's close to the positive tab on the board, but the negative soldering tab is on the other side. Anyway, so far so good. Cozmo is up and running for last few days now with no issues. Haven't timed the battery life, but so far it lasts longer than my son's interest in it for any given moment. Note that it charges quite fast too. So you can play with this thing off and on all day long as long as you park Cozmo on his home charger between plays. Can recommend this battery. And watch John's tutorial too. Happing fixing!

## Features

- Compatible with COZMO Vector robot、 SkyBell HD WiFi Video Doorbell、Flysight FPV Watch、 wireless speaker Battery replacement。Also suitable for DIY electronic products with 3.7-5V and less than 2.294Wh 620mAh built-in 2-wire battery replacement.（★ Not applicable to high-power electric tools and model aircraft）
- Please note that the specifications and polarity of the connector are based on the product display image,★the red wire is the positive "+" and the black wire is the negative "-"，Do not reverse-charge or reverse-connectreverse. ★The primary battery of some products has no plug or mismatched plug or mismatched polarity. It doesn't matter, you can cut and solder the plug directly or use our heat shrinkable insulating sleeve to connect the same color wire.
- 503040 rechargeable lithium ion polymer battery, nominal voltage 3.7V, full charge voltage 4.2V, capacity 620mAh, power 2.294Wh, ★size 5×30×41mm(0.197×1.181×1.598inch）(T*W*L), Weight:13g(0.46oz)，Maximum current:0.6A。 It can prevent overcharge, overdischarge, overcurrent, and short circuit.
- It‘s consists of of large-capacity A+ lithium battery, Japanese Seiko IC overcharge and overcurrent short circuit protection board, 3302-26 high temperature resistant silicone cable, and genuine JST Pitch 1.25mm ★2 wire connector module.
- If there are any quality issues within a year, ★please feel free to contact us via email for replacement.

## Technical Specifications

| Specification | Value |
|---------------|-------|
| ASIN | B08PKV564B |
| Amperage | 0.6 Amps |
| Antenna Location | Doorbell, GPS, MP3 Player, Radio, Speaker, Toys, Watch |
| Battery Capacity | 620 Milliamp Hours |
| Battery Cell Type | Lithium Polymer |
| Battery Weight | 12.6 Grams |
| Battery capacity | 620 Milliamp Hours |
| Battery cell composition | Lithium Polymer |
| Best Sellers Rank | #10,063 in Toys ( See Top 100 in Toys ) #23 in RC Batteries |
| Brand | HXJNLDC |
| Country of Origin | China |
| Customer Reviews | 4.5 out of 5 stars 762 Reviews |
| Item Dimensions | 41 x 30 x 5 millimeters |
| Item Weight | 0.02 Kilograms |
| Manufacturer | HXJN |
| Model Number | 503040 |
| Number of Batteries | 1 C batteries required. (included) |
| Number of batteries | 1 C batteries required. (included) |
| Recommended uses for product | Doorbell, GPS, MP3 Player, Radio, Speaker, Toys, Watch |
| Reusability | Rechargeable |
| UPC | 054114076826 |
| Voltage | 3.7 Volts (DC) |
| Warranty Description | 1 |

## Product Details

- **Battery capacity:** 620 Milliamp Hours
- **Battery cell composition:** Lithium Polymer
- **Brand:** HXJNLDC
- **Number of batteries:** 1 C batteries required. (included)
- **Recommended uses for product:** Doorbell, GPS, MP3 Player, Radio, Speaker, Toys, Watch

## Images

![3.7V 503040 620mAh Rechargeable Lithium Polymer Battery, Suitable for cozmo Vector robot Battery replacement,SkyBell HD WiFi Video Doorbell、Flysight FPV Watch、 wireless speaker Battery replacement - Image 1](https://m.media-amazon.com/images/I/61HDn2M23KL.jpg)

## Customer Reviews

### ⭐⭐⭐⭐⭐ Cumple lo que promete
*by A***N on 4 February 2024*

Una batería pequeña apta para los robots de Anki Cozmo y Vector. En mi caso fue para un Cozmo al que la batería que venía de fábrica no aguantaba ya la carga y era necesario reemplazarla. La batería viene con un conector JST típico en baterías y un pequeño trozo de tubo termorretráctil (que no utilicé). Buena calidad y mayor capacidad que la batería que venía de fábrica con Cozmo. Eso sí, si os aventuráis a desmontar a Cozmo, tened en cuenta que, aunque es relativamente sencillo, hay que hacerlo con cuidado, y la batería tiene que ser soldada a la placa. En cualquier caso, la batería de momento cumple bastante bien y aún no he tenido que cargarla desde que se la coloqué al robot.

### ⭐⭐⭐⭐⭐ Works Great in Cozmo
*by D***. on 24 July 2021*

Works great in Cozmo toys. Perfect fit. Installation isn't too hard but does require some time and patience. See the picture here of my son's Cozmo torn down to the point where the battery can be replaced. It looks like a lot of pieces but everything disassembles easily and goes back together pretty easy too. The head is a little tricky as there is a small spring that you have to fight as you put it together, but isn't too hard once you figure it out. Sort of like a puzzle. There is a video on YouTube by John that is super helpful. Just watch that once and you'll have it figured out. The hardest part for most people will be just soldering the wires to the circuit board. This battery comes with a JST plug, but you have to cut that off, strip the wires, and then solder them to the board. It's pretty trivial if you know how to solder, but could trip up people who've never used a soldering iron. You'll need to cut the red wire shorter and leave the black wire longer, since the leads come out the same side of the battery, so it's close to the positive tab on the board, but the negative soldering tab is on the other side. Anyway, so far so good. Cozmo is up and running for last few days now with no issues. Haven't timed the battery life, but so far it lasts longer than my son's interest in it for any given moment. Note that it charges quite fast too. So you can play with this thing off and on all day long as long as you park Cozmo on his home charger between plays. Can recommend this battery. And watch John's tutorial too. Happing fixing!

### ⭐⭐⭐⭐⭐ Batterie 620mmAh
*by B***K on 14 July 2026*

Parfait merci.

## Frequently Bought Together

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*Product available on Desertcart Greece*
*Store origin: GR*
*Last updated: 2026-08-15*