Bests & Worsts Reviews from Amazon

I specifically bought this particular pump to use in battery mode, as none of the other pumps have that option. This one is considerably more expensive than the others. It seemed to work fine right out of the box, but the first time I took it to the lake, it wouldn't work in battery mode, even though it was fully charged. I had to use it in car charger mode. When I got home I plugged it in to the outlet, and it said 97% charged, and it worked fine, I unplugged it and it worked fine in battery mode. 5 minutes later I tried it again, and no go. It won't work in battery mode, unless you use it within 2 minutes of unplugging it. I've contacted the company, and I'm awaiting a reply from them. I hope we can figure out what's wrong, or that they replace it, because when it worked plugged in, it worked really well! I will update this review when I have something new to report because I had high hopes for this product Update!!!! Important update!! I have changed my review of this product from one star to 4 star. I contacted the seller of this pump, SereneLife's, Customer Service department via their website and asked "is the product was defective or am I doing something wrong?" Their response was to refer me to Amazon for a refund. Wrong answer! What I needed was technical support. I requested a replacement through Amazon and found that the replacement had the same issue. I thought something is amiss here, and I reread the operation manual for the pump and noticed that it mentioned holding the power switch down for 3 seconds after charging the pump. It also mentioned that the LED screen would time out after 2 minutes without pumping to save battery charge. What it DIDN'T mention was that after ANOTHER 2 minutes, the pump would completely power down, and not work again until it's either plugged into a power source, or you hold down that power button for 3 seconds again. Apparently this is what has been happening to many customers, and is the reason for all of these conflicting reviews on this site. It's working fine now, and I'm VERY happy with it. All I needed was someone to interpret the vague and incomplete instructions in the manual. IF THE PUMP HAS BEEN INACTIVE FOR 4 MINUTES AFTER CHARGING, IT WON'T WORK IN BATTERY MODE UNITL YOU HOLD DOWN THE POWER BUTTON FOR 3 SECONDS. Then the LCD screen will light up, push the power button again for a second, and it works great. If it won't come out of the low pressure mode after reaching approx 1 PSI, touch the power button again, and it will kick into high pressure mode. It usually does this automatically, but for some reason it occasionally doesn't. This is a great pump and I'm only giving it a 4 star instead of 5 due to the unclear instructions causing such a hassle and me having to order a second pump, only to have to send it back, after figuring out that the problem was operator error due to poor documentation by the manufacturer.