I bought a SBP 2000 to use it as an UPS (uninterruptible power supply) with better battery life and higher output wattage. It's nearly useless for that though in any long term sense. For some reason in span of 10 minutes maybe less it will fall from 98 (won't charge to 100 anymore) down to one percent maybe all the way to zero without much of any load I think it was 10 watts peak. So about every two weeks I have to shut off the AC outlets on it, unhook everything from it, bring it outside, then connect the solar panels and plug it back into AC out in the garage to try to shock it back to life. I've contacted support through the seller page on Amazon (because it seems to be the only way to get through to them) but all they said was to do the battery charge break in routine. By drain the device recharging it fully then draining it to 50% then charging it. That doesn't seem to solve it though because in the 2 and half months of ownership I've had to bring it out to the garage 5 times. I have said it many times on other threads but this has to be a firmware bug.