KeenPower 6000A Super Capacitor Jump Starter [Upgraded Clamps & Screen Version] – No Traditional Battery, Powered by 6X 3000F Supercapacitors, Works in -45°F Env, 3-Mins Fast Charging for Instant Use

First let me say read the review from Tac Medic.. Second, This is the best jump box EVER!! It is made NOT TO HOLD A CHARGE!!! You charge it by hooking it up to the low battery. If that battery only has 5% this will take a charge from that and basically turn that 5% of power into 100% IE enough power to jump start your vehicle. You can charge back to 100% once the vehicle has started but it WILL NOT hold the charge for more than a day or two. This is my second one because people suck and broke into my jeep and stole my first one!! I used my original in all types of weather and all types of vehicles and it never failed. Even on diesel trucks that require you to wait because of glow plugs. It literally took about 3-4 minutes to fully charge and always started the vehicle 1st time if it was actually a battery problem. Read the directions people!! This will not fail you!!

I've had a lot of battery jump starters over the years and it's a pain to keep them charged up. I started researching options and found this super capacitor jump starter. Little did I know I would need it that week. My car did not start one morning. I connected it up, let the capacitors charge up to 100%, hit the button, and started my car right up. Tried it on my SxS that was dead and it started it right up. Tried it on my 2006 F450 that was dead...worked great. Tried it on my big Diesel RV with completely dead batteries and.... okay, I will say, it started it...sluggish but it started it....however, the cables were EXTREMELY hot and it smoked a little and smelled like it was burning.... so my only suggestion would be to put bigger cables and better clamps that can handle something like a big Diesel. Yes, I have a lot of equipment that just sits and the batteries die. This is perfect for what I need and you NEVER have to worry about keeping this jump starter charged up. It will use the little juice left in your batteries to pull it into the capacitors. I loved this device so much, I purchased a second one, then a third one for a Christmas present for my parents. I highly recommend this jump starter.

This jump box is is a lot more practical for me than the lipo box. This capacitor setup is the way to go for jumping a 12 volt car battery. It is not a portable power bank for charging phones. Capacitors store energy quickly and can dump mega amps all at once. Very quick to charge approx three minutes off a nearly dead 12 volt battery as to where the lipo takes all night to charge . Buy it...you will not regret it!

A little finicky, but it works

I had my doubts, but Project Farm said this was in a league of its own and so I gave it a shot. Tried on a small diesel compactor where I have tried to charge the battery with no luck, so I know it is very much almost completely a dead battery. It wouldn't even charge up this jump box. So I put the box on another charged battery and in about 2 minutes the box was fully charged. Put it on the compactor, pushed the button, waited for the count down and BAM! Started right up! The reviews I have read complaining about this product appear to be from people not using the product as instructed. This thing works unbelievably well. Truly in another league. I hope it lasts for years to come and hundreds, if not thousands, of jumps.

I love this thing. It took a little getting used to but I soon realized that this booster is amazing. In the past I had a 3000 amp Truck pack that worked well but it weighed 40 pounds and was hard to lug around. This booster only weighs about 10 pounds and is easy to use once you figure out how it works. I have jumped several diesel trucks and it really gets them cranking even when they are completely dead. Once the vehicle is started we leave the booster connected to recharge it to 100% so it’s ready to go next time we use it. Only complaint I have is the cables are too short. Would prefer they be longer to make it easier to get hooked up to the battery but it’s not a deal breaker.

I bought this thing on a whim because I like the idea of not having a Lithiom ion BATTERY jumper sitting in the hot car all day (South Florida). Im not one to make reviews until I get to actually test the product and low and behold the battery on my 3.8 liter V6 palisade died on me a week after getting this. There were certain things I wanted info on before buying this so I'd like to relay my answers in case anybody else is interested. 1. I wanted to know how long the charge lasts after charging. I charged it to 100% when received 1/3/26 and kept track every couple of days the percentage. It stayed at 100% for about two days then dropped 2-3% each day. This gives more than enough time to charge then transport to a friend/family member with a dead battery. 2. I also wanted to know if the ability to jump a car at around 5% was true 3. I wanted to know if it could jump start a car WITH NO BATTERY. Low and behold all are true. When changing out my battery I discharged it completely then charged it to 7% with my old battery which registered at 11.2 volts. I then moved the 7% device to my car and jump started it perfectly fine (with NO battery). So far im very happy with it and will likely get a second for my wife's car.

Takes forever to charge via USB but I wouldn't charge anything overnight ,.even my ear buds, so charge it during your waking hours just in case. That being said ,the instructions are terrible, also ,many reviews here don't understand that this isn't a normal battery charger, this uses whatever charge is left in your battery and shoots it back into your battery, well that's my understanding. Check youtube videos on how it works,and make sure you understand what the buttons actually do like the black button and the green button because its very confusing and manual doesn't explain it . Cords could be longer . Plus it doesn't hold charge for weeks. Only get if there's a huge discount or sale,otherwise stay away.