We don't want to discard the waste batteries. Because of the coups circulating in the market: Combine two old waste batteries (such as an electronic wall clock) and you will be able to support them for another few weeks! This is actually not a very good suggestion, but the point is that there are many people doing this! But remember to bring a power test strip. This bauble has a small OLED screen and a light, smart display that tells you how much power is left in the battery. In this way, you don't have to worry about combining two used batteries.
Diamond Segment,Diamond Saw Blade Co., Ltd. , http://www.cndiamondsawblade.com