You can create price alert here, copy coupons and view price history. Best price?
Aliexpress
There’re some similar (or not) items on Aliexpress
Click here to search by yourself. Here are coupons that you can use.
Latest price update (UTC time):
Capaicty 3.0/4.0/5.0/6.0ah, Color Black, Light Integrated L.E.D. Battery Charge Level Indicator, Material ABS Plastic Case + Lithium-Ion Battery, Compatible Compatible Makita 18V Lithium Tools, Battery Type Lithium-Ion Rechargeable Battery, Voltage 18V, Certificate CE / RHOS
Banggood
Banggood warehouse is located in Europe 
. CouponsFromChina software could not find any coupon for this product in Banggood. I don’t want to misguide you about the price. I don’t know if it’s good, because I don’t have enough records in my database…
Link: Banggood product page
Price: $-3
It looks like this item is out of stock in Banggood. If you found it then please send me the link. I will replace it.
Click here to search on Banggood!
Exclusive Allowance Coupons: https://bit.ly/3xWgD9k and https://couponsfromchina.com/short/5cd
Old coupons (from the oldest to the newest): BGHU1160, BG8a6a54, BG8fc505, BG166d3c, BGGines, BGb30b2d, BG18194a, BGa78287, hoNEYbGdeAlS, BGHID18, BGHU2162, BG7e40de, BGd7b70b, BGceaad2, BGTools8, BG1daa7b, BGTACC18, BG38eb06, BG589b2e, BGecdc2c, BGHTT15, BGe7843f, BGd6d4c6, BG027e4f, BG20236Tool, BG8FORMULAMX
(there’s a little possibility that old coupon will work)
Other warehouses/versions
This item is available in 3 another warehouse/versions!
1. China – 18V 6.0Ah Battery For Makita ($33.99)
2. China – 18V 5.0Ah Battery For Makita ($32.99)
3. Europe – 18V 5.0Ah Battery For Makita [EU] ($32.99)
Price history and price alert
Price history is not available for this item (not enough database records)! The lowest price was $29.91 though.
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)).