Go down and check coupons out. Remember to check price history if it is available. What is best price?
Nominal Capacity 5000mAh, Quantity 1PCS, Brand XTAR 21700 Battery, Size 21.5 ± 0.3mm*74.5 ± 0.5mm, Operate Temperature -20℃~60℃, End-of-discharging Voltage 2.5V, Cell INR21700-50E, Standard Charging Voltage 4.2V, Continuous Discharging Current 10A, Nominal Voltage 3.6v, Protected or Not Yes
Aliexpress
There’re some similar (or not) items on Aliexpress
| Image | Product (link) | Price | Coupons |
|---|---|---|---|
 |
XTAR 5000mAh Battery 21700 Rechargeable Battery 3.6V 10A Button Top Li-ion Batteries Cell INR21700-50E BATTERY For Flashlights | $15.98 | – |
Click here to search by yourself. Here are coupons that you can use.
Latest coupon code price check (UTC time):
Banggood
Banggood warehouse is located in China.
Link: Banggood product page
1. ($16.14): BGAlerabat15
2. ($17.09): BGtorch2
just apply this code in your cart after clicking “Proceed to checkout”. Click to copy code and open shop.
Exclusive Allowance Coupons: https://bit.ly/3xWgD9k and https://couponsfromchina.com/short/5cd
Old coupons (from the oldest to the newest): 00c906, BGtorch3
(these coupons are old, so probably won’t work)
Price history and price alert
Check out price history chart (for all/most countries) for XTAR 5000mAh 3.6V 10A 21700 Battery Button Top.
Price records source(s): Banggood
Click on image to enlarge. 
You can set price alert (for Banggood and Aliexpress (only if product name will be the same as on Banggood and I will post it on social media though, so it’s more like Banggood price alert)).