I bought a fat tire scooter from Soversky that had a bad battery pack from sitting too long. They denied warranty coverage so I had a local shop make me a new pack with these cells. Now I have the performance I expected and then some.
Key Features
- Long Runtime Power: 5000mAh capacity supports extended operation.
- Reliable Continuous Output: 9.8A discharge delivers steady, controlled energy.
- Designed for System Packs: Flat top format fits battery modules and welded assemblies.
- Efficient & Durable: Rated for up to 500 cycles with strong capacity retention.
- Externally Protected Use: Ideal for applications using a BMS or protection circuit.
Overview
The Samsung 50E 21700 battery is built for applications that demand long runtime and dependable performance rather than extreme current draw. With its high 5000mAh capacity, it is a popular choice for energy storage systems, electric mobility, and backup power solutions. This unprotected cell is best suited for professionally designed battery systems that manage safety externally.
Applications / Uses
- EV and e-mobility battery packs
- Solar and energy storage systems
- Backup and UPS systems
- Portable power solutions
- Custom battery builds
SPECIFICATIONS
| Manufacturer: | Samsung SDI |
| Model: | INR21700-50E (50E) |
| Size: | 21700 |
| Positive Terminal: | Flat Top |
| Nominal Capacity: | 5000mAh |
| Continuous Discharge Rating (max): | 9.8A |
| Nominal Voltage: | 3.6V |
| Maximum Voltage: | 4.2V |
| Discharge Cut-off Voltage: | 2.5V |
| Protected: | No, unprotected |
| Rechargeable: | Yes |
| Approx. Dimensions: | 21.1mm x 70.7mm |
| Approx. Weight: | 68.7g |
⚠ Important Safety Warnings
Improper handling or misuse of this lithium-ion battery can result in FIRE, EXPLOSION, or THERMAL RUNAWAY, causing personal injury, property damage, or death. Users must read and follow all safety guidelines before purchase and use. Click here to review the full safety guidelines.
- Critical Warning: Never carry loose batteries in your pocket, purse, or bag. Loose batteries can come into contact with metal objects like keys or coins, causing a short circuit, which may result in severe burns, fire, or explosion. Always store or transport batteries in a protective case.
- Intended Use: This battery is designed for integration into protected battery packs with a Battery Management System (BMS) or Protection Circuit Board (PCB). It is not intended for standalone use or for e-cigarettes, vaporizers, or similar devices.
-
Thermal Runaway: A chain reaction where heat from a failing battery
causes further overheating, potentially leading to fire or explosion.
- Causes: Overcharging, short circuits, physical damage, or exposure to high temperatures.
- Prevention: Use a smart charger, avoid damage, and store batteries in a cool, dry place.
- Storage & Transport: Always store batteries in protective cases to prevent accidental contact with metal objects. Never store loose batteries in pockets, purses, bags, or near conductive materials.
- Inspection: Do not use if the PVC wrapper, terminal insulator, or casing is damaged, dented, leaking, or bulging. Continued use could result in failure, fire, or explosion.
- Charging: Use a smart charger specifically designed for lithium-ion batteries and ensure the charger's voltage matches the battery's specifications. Never overcharge, over-discharge, or leave unattended while charging.
-
Prohibited Activities:
- Do not expose the battery to extreme heat, fire, or liquids.
- Do not short circuit, puncture, crush, or modify the battery.
- Do not charge or discharge beyond the manufacturer’s voltage range.
- Do not dispose of in regular trash—always recycle at approved facilities.
- Emergency Response: If a cell shows signs of thermal runaway (e.g., smoke, swelling, hissing, or heat), stop use immediately and, if it can be done safely, move it to a non-flammable surface (e.g., concrete or sand) away from combustible materials. Lithium-ion cells burn as Class B fires — use an ABC / dry-chemical fire extinguisher, or douse with large amounts of water to cool the cell and prevent the fire from spreading. Do not rely on a small spray; thorough cooling is required, and cells can reignite from residual heat, so monitor the area afterward. (Class D extinguishers are intended for lithium-metal batteries, not lithium-ion.) For any fire beyond a single small cell, evacuate and call emergency services.
Disclaimer
18650Battery.com is not responsible for any damages, injuries, or claims arising from improper use, handling, or failure to follow these safety guidelines. Lithium-ion batteries require strict adherence to all safety protocols. It is the reseller's responsibility to ensure all safety warnings and product guidelines are effectively communicated to customers. Users and resellers assume full responsibility for the safe handling, usage, and distribution of this product.
Customer Reviews
Overall rating: 4.8 / 5 from 103 reviews.
Working well with flashlights and etc, that needs low amps and does not require a lot of power. These are an excellent battery I highly recommend them. Easily charged up doesn't take long, so all in all these perform if I was to rate them it would be a 4 out of 5 stars.
Just got four 21700 batteries rated at 5,000mAH and graded them with a XTAR VC8 charger/capacity tester. The actual capacities of the 4 batteries range from 4,759; 4,808; 4,948; and 4,982mAH, which is equivalent to 95.2% to 99.6% of advertised capacity, or an average of 4,874mAH or 97.5%. Amazon or eBay will sell you stuff that's not even close. I'm happy with my purchase.
Ordered tool battery kit except cells online. Ordered 5000mAh 21700 cells from 18650battery.com and welded up nice replacement 10Ah battery pack. Tools are happy, I’m happy.
Great battery
Shipping was fast and the items as described extremely happy with this purchase, will buy again!
Not much to say, service as it should be.
Rebuilt battery pack for my electric unicycle.
Every cell I've purchased has passed incoming inspection tests for capacity and internal resistance.
I always have the best experience when dealing with 18650 Batteries. Their shipping via UPS eliminates all the heartache and headache I get from Federal Express and USPS....
Love the product super fast delivery
All as expected!
Work great!
They work.
Great Service. Thank you.
As described. Very good
So far so good.
Genuine to the labels. Awesome batteries and awesome prices with fast shipping. What's not to like.
I'm happy
Great product and service. Thank you.
As advertised
Good items as expected and prompt service
Great purchase. I have the power batteties needed installed working fine.
received battery quickly. Battery was partially charged which is how you are supposed to store Lithium batteries. Charged up and works great in flashlight.
Batteries arrived with a charge of 3.0v. I have not yet checked internal resistance or max capacity but im still very disappointed to receive them in that condition.
Great
👍
good]
Just what I needed!
Cramped it into a Gearlight S1000. So far they work great. Does add more weight than I expected.
As advertised
Great batteries for my vape at a great price. Thank you!
Worked as expected
Batteries work great.
I have always been pleased with the pricing and service! These are great cells at a very reasonable price.
Batteries are of good quality and capacity is as good or better than stated on website.
Batteries arrived on time and in excellent condition and 50% off was really nice too!
Samsung is the best company.
The wrong batteries were sent
I’m just starting to gather the materials I needed for my project.