Replace batteries in my Jackery?

Hello everyone!

I bought a Jackery Explorer 300 in 2021 for camping trips. Since then it has remained plugged in and used to charge other devices, which I think is what may have lead to the current problem. Once unplugged from the wall the display goes from reading 100% to nothing, because it slowly turns off, the numbers do not change and it will not turn back on. Once the power cord is returned then it will start at 0%, but then quickly jump straight to 100%. I have tried leaving it unplugged and I've tried resetting it. No difference.

If it is true that the batteries can no longer hold a charge, then I'd like to replace them. I am no stranger to such repairs, but I haven't worked on one of these before. If I do it perfectly, there shouldn't be any problem with simply replacing the packs of 18650's with some new packs, right? I'm assuming that they put out 12v.

Thank you in advance!

IMHO, upgrade to something with LFP. You're throwing good money after bad investing hours of your life you can't get back, and you'll find yourself right back here in a couple years.

Check youtube. I have no idea what is in there.
This doesnt sound like a battery problem to me tho....
It sounds like the charging logic cant see the battery.
It could be anything at this point

I will upgrade later, in fact I will build a lifepo4 based backup. But for now, I want fix my Jackery and I'm looking for some reassurance from someone that has replaced the cells, or knows that replacing the cells shouldn't be an issue.

It is very worthwhile to attempt to repair your aging jackery unit ... what you'll typically find is:

1. it may not be easy at all, because Jackery didn't design it for ease of repair; it's why we want right to repair laws, so something like replacing a battery isn't the end of the world. Look to youtube and ifixit for teardown and/or repair vids and steps for your model, or basically, search the internet for such help.

2. you might find, even if you get it apart successfully, that something else is broken (besides the battery). But, I still think it is a worthwhile venture, if you are the least bit handy and diy-natured. you'll typically need basic hand-tools only, and possibly a specialized bits kit (if jackery used "security" screws and such). It's your hours, and it does help you recycle things, vs just tossing them into the dump.

3. once it's apart, you can better decide if it's battery (a single block, or 18650s, or whatever) are worth replacing. Sometimes you can't tell until you get in there.

I recycle such stuff (electronics, appliances, etc.) all the time, and usually have about a 1/3 repair rate or better ... when it's just the least bit apart, you usually find some problem that is very fixable. the next 1/3 is a smoking gun of a busted/fried part (the part is actually "smoked" or fried), and there's no fixing it, plus no easy way of getting parts anyway. The final 1/3 is the "mystery" problem ... who knows what part (usually electronic) no longer works.

In any case, these efforts also help me decide if the vendor gets repeat business or not ... if it's so cheesy that it fails in every category (parts, mystery problems, totally useless or very short warranty, etc.), then I know to stay away from them forever.

Hope this helps ...

This thread indicates that someone did attempt a battery replacement (individual battery cells, internal fuse), and supposedly had good luck with the process:

diysolarforum.com/threads/jackery-explorer-500-bms-identify-replace.56091/

Some encouragement, there ...