I have checked all old coupons and price is 63.99 USD for 15.2V 9000mAh 100C 4S (in Banggood). You can create price alert here, copy coupons and view price history. Let’s see what best price is ATM.
Latest price update (UTC time):
Banggood (63.99 USD)
Banggood warehouse is located in China. Hmmm… There is no active coupon in Banggood at this moment. Low/high price? From what I can see this price is higher than average price (43.85 USD).
Link: Banggood product page
Price: 63.99 USD
Exclusive Allowance Coupons: https://bit.ly/3xWgD9k
Old coupons (from the oldest to the newest): Cuponation9, BGMatt2022, BGToys8, BGGutscheine, BG8OFFCOUPON, TTBLACK5, BGSaleFeb8, BG589b2e, BG8FORMULAMX
(these codes were not working in latest coupon update, but you can check them out anyway)
Aliexpress
Click here… to search for ZOP Power 15.2V 9000mAh 100C 4S RC Battery on Aliexpress
Here are coupons that you can use.
Price history and price alert
Check out price history chart (for all/most countries) for ZOP Power 15.2V 9000mAh 100C 4S RC Battery.
Price records source(s): Banggood
Click on image to enlarge. 
You can set price alert (for Banggood).