Protection Mode: Short Circuit Protection; Over-Current Protection; Reverse Connection Protection, Input current: Li-ion 2000MA*1 / 1000MA*2 / 500MA*3 / 500MA*4, Safety Protections: DV Detection; ODV Detection; Total Time Control; Highest Voltage Detection, fire proof material, Loading spring: Military grade spring, Working Temperature: 0-40 Celsius, Case Material: ABS +PC, Input: DC 5V /2A, Idling Output Voltage: 5V, NiMH 1.2V 500MA*1 / 500MA*2 / 500MA*3 / 500MA*4.
Go down and check coupons out. Remember to check price history if it is available. Let’s see what best price is ATM.
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 coupon and price update (UTC):
Banggood
Banggood warehouse is located in China. Well, there is one coupon available right now.
Link: Banggood product page
1. ($30.40): BG589b2e
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 and https://couponsfromchina.com/short/i1u
Old coupons (from the oldest to the newest): BGI4, BCNLXK, BG13TH, F7BG, BGff2020, BGTBD, BG1128, BGYW01, BG10OFFAFF1, BGTorch4, BGdeals308, 00c906, BGtorch2, BGtorch3, BGCL56, BGAlerabat15, BGCL61, BGtorch7, BGAlerabatI, BGtorch9, BG8Alerabat, BGLED07, BGOutlight10
(sometimes old coupons work, so you can check them out (this site checks them on every price update))
Price history and price alert
Here is price history (for all/most countries) for GOLISI i4 Battery Charger. The lowest price was: $14.13.
Price records source(s): Gearbest, 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)).