Li-Ion battery jump starters - any experience out there?

[FJR Colorado]

OK, so let me as THIS, then: What if I did it the other way around? Has anyone done that?

What I mean is this: My biggest worry is being out somewhere solo and having a dead battery that won't start my vehicle. So, if I get one of these LiFEPO4 jump packs, keep it fully charged while I'm driving. When I get to my campsite, I disconnect the fridge from the vehicle's 12v outlet and plug it into the LIFEPO4 charger. Assuming I get to camp around 4pm, would one of these little chargers be able to run a 41qt fridge until morning? Because if so, I could just connect the fridge to the charger when I'm stopped and then I would be pretty certain my truck would start (since there wouldn't be anything to drain the battery at night) and when I took off the next morning, I could recharge the jump pack via the 12v outlet.

I don't have any experience with LiFEP04 jump packs, but I can tell you that that for normal jump packs with sealed lead acid batteries this should work just fine. I have a remote off-the-grid cabin. I bring a jump pack fully-charged and can run LED lights for several nights. If I run the jump pack down by using it for other things, I can easily charge it while driving using the cable with male cig adapters at each end.

BTW, LED lights really changed things for me. I remember how this process was such a daily chore back in the 90's running incandescent lights at night. I almost CAN'T run the jump pack down with the LED lights. Phenomenal.

Maybe here is the best solution of all for you:
-When driving, run fridge off car
-At night, run it off a bulkier sealed lead acid jump back (runs about $70 at AutoZone)
-Use a lithium small jump pack as your ultimate safeguard should you need a jump (it should hold a charge for 6 months or more and use minimal space)

That way if your car dies, and you exhaust the cheap jump pack overnight with fridge & lights use, you still have an ace up your sleeve...

 

[BigSwede]

Those little LiFePO4 jumpstarters claim 11-13 amp-hours from what I have seen, which is marginal at best to run a fridge overnight, and almost certainly insufficient if ambient temps are high.

After looking seriously into a dual battery system, I ultimately backed away and instead managed to fit a 100 amp-hour Group 31 Sears Platinum into my Trooper as a single battery, with a LiFePO4 jumpstarter as backup. This setup should work fine for overnights running my fridge and CPAP and whatnot.

 

[nocean]

I use a Odyssey battery for my main start and car battery. I run my fridge full time when in use, external lighting, LED light strip for cooking, and USB ports for phones and cameras all off my main start battery. I have the Micro-Start as my just in case battery. I also used it to jump start an old quad about two dozen times recently that had a bad battery. And if I feel like it, I have a Goal Zero battery kit that just connects to the Odyssey directly with my solar panel outside to top things off on hot days. I have never run out of juice on this set up and been quite happy with it. Simple, small, and keeps me away from having to run a 2nd battery system which are expensive and can without notice fail.

 

[Schattenjager]

Chance favors the prepared mind! And yes, I have used the little lithium ion pack / kit I found at Fastenal twice now on a friends car. Worked impressively well. Remember that they will not like long exposure to cold. I keep mine under my drivers seat. Its amazing that this little unit can out power by beloved Xantrex Power station complete with 110 inverter. The Xantrex still goes out with me as a backup to the backup, but the small light weight size makes this new addition my go to power source.

 

[Weeds]

I have the Micro-start. It is good at what it is supposed to do, start vehicles. It will run and charge your ipod, phone, laptop. Peterson's 4wheel and off road magazine had a favorable review after a year testing. The review should be available on line.

 

[BlueCruiser88]

I have the zero Gravity Jump pack.

It works...it replaces a heavy lead acid jump pack... it fits in the glove box...a no brainer purchase if you need the space and weight savings. Tons of adapters to save a friend who forgot a phone charger (if your phone dies your life ceases to exist now days)

Makes a great stocking stuffer too!

 

[Quniet]

Just my two cents...
I have been really tempted to buy one of these, because I think they are neat, not that I actually need one. Perhaps for jumpstarting others, as I do not carry cables, nor am I always willing to move my vehicle in such a manner as to jumpstart another. I also would not allow another person to handle the cable ends, as far too many do not understand polarity and will fry the donor vehicle with their ineptness..

As with lead acid batteries, the number of cycles depends on how they are treated. Lithium batteries actually degrade faster when stored at full charge. Lithium batteries also lose a bunch of capacity in cold temperatures. more so than lead acid batteries.

These lithium packs should also not be left to roast in a closed vehicle in summertime.

Some of these claim to be Lifepo4, and others that do, likely use 18650 Lico cells, like are in most laptop batteries and Tesla vehicles. The LiCo can be more energy dense, the LifePo4 safer. I have not yet found any websites where one of these units is dissected and closely inspected.

If any Lithium battery catches fire/starts smoking, the fumes are very toxic with lung damage likely if in an enclosed vehicle. Fires are most likely when charging, and charging of batteries that have been over discharged. While fires are not common, they cannot be ruled out as a possibility. Lead acid batteries can explode too. I do not know how effective the BMS's are inside these jumper packs to keep them from overcharging or overdischarging, or disconnecting them if the cells get too hot, or vary too widely in their voltage. All lithium battery packs that have multiple cells have to employ some sort of BMS( battery management system)

There are many many brands of these lithium jumper packs https://10carbest.com/best-jump-starters out there, and more everyday, and most all of them way overstate their capacity. There are a couple Amazon reviews by those with the knowledge and the tools to test capacity, and one of these 11000 mah packs measured out at just over 2000 when brand new. Even if they claim 11000 mAh at 5 volts instead of 12+ volts, these Mah numbers are unrealistic.

I don't really know how fast these charge from a USB source, or a 12v source. I don't know how well they would respond to being treated as a small house battery. Do keep in mind how small they are. They are smaller than my 9 cell 18650 laptop battery. I am guessing that most of these jumper packs are using Six 18650 cells which are capable of high discharge current. While the highest capacity 18650 cells are 3400mah at 3.7V, high discharge cells are usually about 2100Mah, and as such, I think any claim of capacity over~ 6300 is unrealistic, and that is at 3.7v, not at 12v.