LiPo battery sparks when used with DC step up convertor

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I’m using a LiPo battery 700mAh 3.7V with MT3608 DC-DC step up boost converter module 2V-24V 2A.

The problem is when I connect these to anything or even the wires just touch each other they produce a spark. I want to hide or remove them so that it doesn’t harm my ESP32. Also is there any way with which I can reduce the current of the output from the battery?batterieslipobuck-boostshareedit  follow  flagedited 17 mins agoJRE39.5k88 gold badges7070 silver badges114114 bronze badgesasked 1 hour agoanimesh1111 bronze badge New contributor

• 1All step-up converters spark unless you have soft start. Do you understand transformed equations for V,I,Z ratios? – Tony Stewart Sunnyskyguy EE75 1 hour ago 
• 1@TonyStewartSunnyskyguyEE75 What is a soft start, sir? Please tell me about it, I’m still learning. I don’t know much about Transformed eq. – animesh 1 hour ago
• 1@TonyStewartSunnyskyguyEE75 And also please tell how I can reduce the amps in the circuit? Thanks – animesh 1 hour ago
• Ah, let me see. When your LiPo connects/touches the MT3608 guy, there will not be any spark yet. It is only when you disconnect (breaks the circuit), then the scary spark jumps out. A couple of solutions: (1) Use a little manual power switch, eg, 125VDC, 2A to power off off the Lipo power bank. The way, the spark still jumps out, but at the power switch contacts, and some how “kills/absorbs” by the little manual power switch. – tlfong01 9 mins ago   
• 1@animesh what do you have connected as a load on the 24 volt output? What are your expectations of maximum load current on the 24 volt output? – Andy aka 7 mins ago
• This is an example of the power switch I am referring to: Miniature Rocker Switch / Single pole Double throw SPDT 120VAC 6A – US$2 (10 pcs) fr.aliexpress.com/item/…. Acutally you can use any other similar power switches under 125V 2A. – tlfong01 3 mins ago   
• This is the MT38608 module schematic, for our future discussions.:mt3608stepupmodule.files.wordpress.com/2017/11/… – tlfong01 19 mins ago   
• Another precaution you might to take is the following: (2) Do not connect the load before setting up and switch on power, to avoid big rush of current when you switch on power. Also you can start with a small test load, and increase loading gradually, or in small steps, to verify if the big load is making the trouble. I know ESP32 takes very little current, but are you also connecting a BLDC motor to the boosted up 24VDC? – tlfong01 12 mins ago   
• Another general trick is to use “delay start up” circuit. The idea is first switch Vcc/Lipo power, by using a cap to delay the MT3608 PSU enable signal. The red square in the following LM2596 PSU shows how to do it. (3) i.imgur.com/Z582tZe.jpg. WARNING: Me just a friendly hobbyist, no guarantee no nothing would melt down or blow up. Good luck and cheers. – tlfong01 3 mins ago   Edit   

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