Aliexpress
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
Coupon (30.80 USD): BGGAL8
Coupon (30.80 USD): BGRCParts8
(CouponsFromChina.com tip: paste coupon code in your cart and click Apply after clicking “Proceed to checkout”. Click to copy code and open shop)
Exclusive Allowance Coupons: https://bit.ly/3xWgD9k
Old coupons (from the oldest to the newest): BGURUAV17, PU15, AFfbG10, BGVDay10%off, BGBCPRO1, bGhOnEy10, BGBC1, BGAFF10OFF, BGCuponation10, BGBCSpring1, BGDAVIS, BGHONEY2110, Parts8, BGRCBC11, BGSFBC1
(I don’t think these’re gonna work, but you can try ’em out anyway)
Price history and price alert
Do you need price history chart (for all/most countries) for URUAV 14.8V 1800mAh 75C 4S RC Battery? There we go.
Price records source(s): Banggood
Click on image to enlarge. 
You can set price alert (for Banggood).