Test results LiFePO4 glider batteries after 6 years

On Thursday, March 9, 2017 at 6:16:51 PM UTC-8, SF wrote:
Yes worth it. Higher voltage will be appreciated by the radio. More capacity.
Lighter weight, longer life.
Not really a hassle with the right charger, just a little different.

The thread has inspired me to test my LFPs.

3 year old Starkpower 12AH used for instruments, 11.86AH (tested to 11V @ 1.5A). This improved to 11.91 on the second cycle.

3 year old Starkpower 9AH used for self rig wing dolly, 8.60AH (to 11V @ 1A).

2 year old CTC 19.8AH used for engine start, 19.38AH (to 11V @ 2A). I may give this one a second cycle to see if it improves.

While I was at it, a 5 year old PowerSonic 14 AH SLA, 9.8AH (11V @ 1A). This battery had been sitting idle and uncharged for 3 years, till I charged it for the test.

The SLA had a nearly linear drop from 12.8V to 11V, dropping under 12V at about 60% discharge, while all of the LFPs stayed above 12.5 until about the 90% discharged point.