Stanley Fat Max 700 won't take a charge

I had a similar problem with my 5 year old jump box with a compressor. The problem is that there is a small sealed 12v battery inside your jump box. It looks like a little car battery and it goes bad in 3-5 years just like the a 12v battery in most cars.

Simple fix is to OPEN the box up, note the size of battery and type of posts and buy new battery for the inside of the box (Amazon).

To replace the battery is 1/2 cost of a new jump box ! NOTE: You have to get same posts to get it to fit in box

 

Any idea what kind of battery is in it? Maybe you can open it up and check the battery and -- depending on the kind -- replace it if it's dead. May or not be worth it.

 

How old is it, and how many cycles have you put it through?

It sounds like the SLA battery is going south.

 

Even jumper batteries fail and have limited life cycles just like car batteries. Example: I’ve replace the battery in my Roomba 3 times in its life.

 

Yeah similarly, I see there's a replacement battery available at Canadian Tire, for my Clore JNC660. I think it's this one:

12-Volt 18AH SLA Battery | Canadian Tire

US link, better amp hours, cheaper:

JNC660 Jump Starter Jump N Carry Battery (12V 22Ah)

 

The way it sounds, leads me to think the charge module is no good. You need to do some test to see if the charger might be your problem. It may even have a fuse that’s bad.
The charge itself is just a normal ac 12v wall charger that’s mounted inside the outer cover.

 

You might want try a different cord. See what happens.

 

I have 2 older jump boxes that served me well then stopped working. I will dig them out and do some dissecting and replace a battery or 2.
I have a hand held spotlight that recently stopped working. Rather than tossing and buying new, I just this week tore into it and found it was powered by a single 2200ma 18650 cell. Ordered a replacement 3000ma cell off of Ebay for a few dollars and plan to get it back into service. Dont know why I never thought of replacing the battery in those jump packs. Thanks!

 

Sometimes battery replacement can rival (or exceed!) replacement cost. I did a battery replacement on a cordless phone set, that was like that. Still, you've kept something useful out of the recycle stream (or landfill...), and it's an item you're familiar with, don't have to have to relearn how to use something new.

 

The battery charges the capacitor, low current/voltage.
It give a huge burst to the dead battery and usually it's enough to start the car
in 1 second then the device shuts off so it doesn't damage the small 12v battery.

The small terminals are not a problem. With the connector, there is only a small portion
that actually touches.

 

With my JNC660, there's "compatible" batteries available on Amazon, for around $40~60. Clore (the jump pack manufacturer) offers an "official" battery on their website for around $160. That battery can also be found on Amazon, for around $110.

The specs on the Clore sanctioned battery, amp hours in particular IIRC, are higher than the cheap batteries. This may well be an instance of "you get what you paid for". Considering the new jump pack goes for around $200, and the original batteries seem to last up to 10 years, if/when I'm in need of a replacement I'll probably stick with the sanctioned replacement battery, though I will look for best price.