08-14-2016, 06:21 PM
(08-13-2016, 02:20 AM)MarkHaysHarris777 Wrote:(08-13-2016, 02:09 AM)pfeerick Wrote: Well, my generic 8000mah battery seems to be no-where near it's rated capacity - is lasting about half the time I would have liked (basically overnight). I had intended to make it so the pine64 was charged from solar when the sun was up, and run from the battery overnight, but the battery is only just making it overnight, so won't last long with that near total usage, and doesn't leave any room for the pine64 do actually do some work.... this was with the pine64 idling.
hi pfeerick, I am working with SLA batts at the moment. I posted in the DC POWERIN subforum; I'm using the CPT module I received from Pine. I built a low_pass filter ( PI ) and have been playing around with powering via 12v on via CPT via PI filter on the euler buss.
My interest of course is robotics. I need some beefy batts for the 12v motors I'm going to use, plus I need it to keep the electronics up (for several hours, while the robot patrols the house).
But, I was thinking the 12v system is the answer to a solar system also. The lith-ion batts aren't going to cut it, but a bank of 12v SLA batts I think is just the ticket. Let me know what you think.
Yeah, the flat lipo batteries that claim to be for tablets are pretty useless at best. This one I have here, which should just about last 24 hours is now down to about 8 hours, so pretty pathetic. I've had much better luck with the 18650 (cylindrical) lithium batteries - they can provide a lot of current in a short time if you need it, or can simply potter along.
If you're system needs 12v due to the motors, I'd go with either the 12v SLAs you have if the weight isn't an issue. If you want less weight, a 3S lithium setup is the way to go. Stick the 18650s as they are easy to get hold of, and if you use cell holders, can be replaced as easily as AA batteries. There are plenty of protection circuits you can get that will stop the cells being over or under charged, and automatic chargers (as in plug in and it charges) for them are pretty cheap also. Either way, since you're making a roving robot, I'd be also trying to work out how to make an automatic charge dock (like the Roomba) that it can trundle back to when it's starting to get flat.
