I’m figuring seven 26650 (3.7V, 5000mAh) batteries in series (~26V, 5Ah) x4 in parallel (~26V, 20Ah) would keep a Netonix switch, two backhauls, and an AP or two up for 8 hours with a power draw ~2.5A @ 24V and use significantly less weight and space.
Chris Wright Network Administrator From: Af [mailto:[email protected]] On Behalf Of Harold Bledsoe Sent: Thursday, June 22, 2017 12:23 PM To: [email protected] Subject: Re: [AFMUG] Li-ion Battery Backup And if you don't charge it right.... ;-) On Thu, Jun 22, 2017 at 3:11 PM Bill Prince <[email protected]> wrote: Depending on how you figure li-ion battery voltage (I use 3.7 volts per cell; I've seen some others say 3.6 volts per cell), it will take 13 li-ion batteries to make 48 volts. The big issue that I can imagine is that li-ion have a completely different charging profile from SLA batteries. I don't know whether it would be better to try to build an array at 48 volts, or go for something much larger (say 480 volts), and do a DC-DC converter to get whatever voltage you want on the other side. This will be an interesting discussion. bp <part15sbs{at}gmail{dot}com> On 6/22/2017 11:36 AM, Chris Wright wrote: Lithium Ion batteries are getting so cheap these days it�s tempting to fabricate a battery bank out of them and use them for backup power. Do they behave well with constant voltage running through them supplied by a typical Mean Well AC to DC Converter, or would a special maintainer with an automatic transfer switch be required? � Chris Wright Network Administrator �
