--- product_id: 261798251 title: "HXJNLDC DC 3.7V 620mAh 503040 Rechargeable Lithium Polymer Battery for Cozmo ..." brand: "hxjnldc" price: "109.29 DT" currency: TND in_stock: true reviews_count: 13 url: https://www.desertcart.tn/products/261798251-hxjnldc-dc-3-7v-620mah-503040-rechargeable-lithium-polymer-battery store_origin: TN region: Tunisia --- # 3.7V nominal voltage, 4.2V max charge 620mAh high-capacity power Built-in overcharge & short circuit protection HXJNLDC DC 3.7V 620mAh 503040 Rechargeable Lithium Polymer Battery for Cozmo ... **Brand:** hxjnldc **Price:** 109.29 DT **Availability:** ✅ In Stock ## Summary > 🔋 Power your smart life with confidence and style! ## Quick Answers - **What is this?** HXJNLDC DC 3.7V 620mAh 503040 Rechargeable Lithium Polymer Battery for Cozmo ... by hxjnldc - **How much does it cost?** 109.29 DT with free shipping - **Is it available?** Yes, in stock and ready to ship - **Where can I buy it?** [www.desertcart.tn](https://www.desertcart.tn/products/261798251-hxjnldc-dc-3-7v-620mah-503040-rechargeable-lithium-polymer-battery) ## 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 - • **Safety-First Design:** Integrated Japanese Seiko IC safeguards against overcharge, overdischarge, and short circuits—peace of mind included. - • **Reliable Power Boost:** 620mAh capacity fuels your devices longer, keeping you connected and productive. - • **Universal Compatibility:** Perfect replacement for Cozmo Vector, SkyBell HD, Flysight FPV Watch, and other 3.7-5V devices under 2.3Wh—versatility that fits your tech ecosystem. - • **DIY Friendly Installation:** Includes heat-shrink insulating sleeve for easy wire splicing—no plug? No problem. Customize your connection with confidence. - • **Precision Voltage Control:** 3.7V nominal with 4.2V max charge ensures stable, efficient energy delivery for sensitive electronics. ## Overview This 503040 rechargeable lithium polymer battery delivers 620mAh at 3.7V nominal voltage, with a max charge of 4.2V and 0.6A max current. Designed for compatibility with Cozmo Vector robots, SkyBell HD WiFi doorbells, Flysight FPV watches, and similar low-power electronics, it features advanced Japanese Seiko IC protection against overcharge, overdischarge, and short circuits. Compact (41×30×5mm) and lightweight (13g), it includes a heat-shrink insulating sleeve for easy DIY installation, making it the perfect reliable replacement battery to keep your smart devices running longer and safer. ## Description 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 ## Features - Compatible with COZMO Vector robot SkyBell HD WiFi Video Doorbell Flysight FPV Watch wireless speaker Battery replacement。It can also be used in other 3.7-5V electronic products with power less than 2.3Wh (620mAh).（★ Not applicable to high-power electric tools and model aircraft） - Please compare the connector specifications and polarity according to the display diagram before purchasing,★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 2.29Wh, 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 Pitch1.25mm 2-pin 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 | |---------------|-------| | Amperage | 0.6 A | | Antenna Location | GPS, Radio, Watch | | Asin | B08PKV564B | | Battery Capacity | 620 milliamp_hours | | Battery Cell Type | Lithium Polymer | | Battery Weight | 13 g | | Brand | HXJNLDC | | Customer Reviews | 4.4 4.4 out of 5 stars (806) 4.4 out of 5 stars | | Included Components | 620mAh battry x 1 pack, heat shrinkable insulating sleeve x 1 | | Item Dimensions | 1.61 x 1.18 x 0.2 inches | | Item Weight | 0.02 kg | | Manufacturer | HXJNLDC | | Model Name | 503040 | | Model Number | 503040 | | Number Of Batteries | 1 C batteries required. (included) | | Reusability | Rechargeable | | Unit Count | 1 Count | | Upc | 054114076826 | | Voltage | 3.7 volts_of_direct_current | ## 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:** GPS, Radio, Watch ## Images ![HXJNLDC DC 3.7V 620mAh 503040 Rechargeable Lithium Polymer Battery for Cozmo ... - Image 1](https://m.media-amazon.com/images/I/61HDn2M23KL.jpg) ![HXJNLDC DC 3.7V 620mAh 503040 Rechargeable Lithium Polymer Battery for Cozmo ... - Image 2](https://m.media-amazon.com/images/I/71qZeb1kqsL.jpg) ![HXJNLDC DC 3.7V 620mAh 503040 Rechargeable Lithium Polymer Battery for Cozmo ... - Image 3](https://m.media-amazon.com/images/I/81jSmvePDIL.jpg) ![HXJNLDC DC 3.7V 620mAh 503040 Rechargeable Lithium Polymer Battery for Cozmo ... - Image 4](https://m.media-amazon.com/images/I/81ygEeonPJL.jpg) ![HXJNLDC DC 3.7V 620mAh 503040 Rechargeable Lithium Polymer Battery for Cozmo ... - Image 5](https://m.media-amazon.com/images/I/616ocrZc8aL.jpg) ## Available Options This product comes in different **Color** options. ## Customer Reviews ### ⭐⭐⭐⭐⭐ Works Great in Cozmo *by on Reviewed in the United States July 24, 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! ### ⭐⭐⭐⭐⭐ Nice replacement for my Skybell HD V4 *by on Reviewed in the United States August 9, 2022* Bought a house with an expensive Skybell HD V4 Video Doorbell. The thing was working in short bursts, couldn't figure it out. Checked the connections, all was good. Found that the battery on these would expand and die, and that's what happened to mine.I pulled mine apart and found I needed a new battery. I found this replacement on Amazon. Don't do what I did....I threw out the old one before the new one arrived. The plug is not an exact match. You need to splice the wires from the old battery to the new one. The plug is slightly different.Since I didn't have the new one, I improvised. I followed my college engineering training.Step 1: Is it working now? NoStep 2: Does the part jam? Yes, the plug doesn't fit cleanly.Step 3: If this battery doesn't work, whats the alternative? Spend $250 for a new doorbellStep 4: Follow the old adage of:If it jams, force it, if it breaks, it needed fixing anyway.I jammed the plug into the socket on the camera using a pair of needle-nose pliers and got it working. The doorbell has been working the last month without issues. I would call this battery a replacement, even if it was a bit more difficult due to me shooting myself in the foot throwing the old one away before I took the plug. ### ⭐⭐⭐⭐⭐ Great Replacement for Anki Cozmo in 2024 *by on Reviewed in the United States January 7, 2025* Worked great to replace my failing Anki Cozmo battery from 5 years ago. The double capacity is a great plus, although you'll probably get bored before it dies anyways. It does take slightly longer to charge though with the larger capacity, about 2 times longer.Would recommend for anyone who wants to replace their failing Anki Cozmo battery! ## Frequently Bought Together - HXJNLDC DC 3.7V 620mAh 503040 Rechargeable Lithium Polymer Battery for Cozmo Vector Robot SkyBell HD WiFi Video Doorbell Flysight FPV Watch Wireless Speaker Battery Replacement - PKCELL N Size 1.5V Alkaline Batteries, 10 Pack Ultra Long-Lasting MN9100/E90/LR1 Medical Battery for Medical Devices, GPS Trackers, Flashlights, Key Fobs, 10-Year Shelf Life - Duracell N 1.5V Alkaline Battery, 2 Count Pack, N 1.5 Volt Alkaline Battery, Long-Lasting for Medical Devices, Key Fobs, GPS Trackers, and More --- ## Why Shop on Desertcart? - 🛒 **Trusted by 1.3+ Million Shoppers** — Serving international shoppers since 2016 - 🌍 **Shop Globally** — Access 737+ million products across 21 categories - 💰 **No Hidden Fees** — All customs, duties, and taxes included in the price - 🔄 **15-Day Free Returns** — Hassle-free returns (30 days for PRO members) - 🔒 **Secure Payments** — Trusted payment options with buyer protection - ⭐ **TrustPilot Rated 4.5/5** — Based on 8,000+ happy customer reviews **Shop now:** [https://www.desertcart.tn/products/261798251-hxjnldc-dc-3-7v-620mah-503040-rechargeable-lithium-polymer-battery](https://www.desertcart.tn/products/261798251-hxjnldc-dc-3-7v-620mah-503040-rechargeable-lithium-polymer-battery) --- *Product available on Desertcart Tunisia* *Store origin: TN* *Last updated: 2026-08-16*