Plug: XT60 Plug, Capacity: 1800mAh, Battery Parameter: TATTU 14.8V 1800mAh 120C, Colors: Standard Colors, Continuous Discharge Rate: 120C, Size: 78*39*38mm, Weight: 191g.
Just check coupons out (with price alert and history). Best price?
Aliexpress
There’re some similar (or not) items on Aliexpress
You can use link bot to get even lower price:
Click here to search by yourself. Here are coupons that you can use.
Latest price update (UTC time):
Banggood
Banggood warehouse is located in China.
Link: Banggood product page
1. ($47.80): BGGAL8
2. ($47.80): BGRCParts8
3. ($47.80): BG8RCToy
4. ($47.80): hoNEYbGdeAlS
put item in your cart and apply coupon code there after clicking “Proceed to checkout”. Click to copy code and open shop.
Additional Banggood coupons: first page and second page
Old coupons (from the oldest to the newest): PU15, AFfbG10, BGCITYADS2019, BGVDay10%off, BGBCPRO1, bGhOnEy10, BGBC1, BGdragonBoat, BGRCBC7, BGSS10%SW, bgshOOp10, BGRC902, BgoFErTaSchInA10, BGTATTU4S, BGHALLOWEEN, BgcLuBofErtA10, BGAFF10OFF, BGCuponation10, BGDAVIS, BGHONEY2110, Parts8, BGRCBC11, BGSFBC1, Tabby20, BG1efeb0, 8Couponsde, MVC8SPRING, 8BGwbg2204, tRaDetRaCKeR, 8wEbgaInS5, pROMo8cuPoN
(these coupons are old, so probably won’t work)
Price history and price alert
Do you need price history chart (for all/most countries) for TATTU R-LINE V3.0 14.8V 1800mAh 120C 4S RC Battery? There we go. The lowest price was: $26.39.
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)).