Copying the following great post here which was written by _Cy_, over on ADV in the big battery thread:
http://advrider.com/index.php?threads/motorcycle-batteries-agm-gel-wet-lithium-iron-phosphate-lifepo4.757934/page-124
- CW
How to put away a battery for the winter:
this is for folks with AGM and LiFePO4: all voltages need to be taken with a known to be correct meter.
for sloosh PB those will need some type of trickle charger which is NOT recommended for AGM/LiFePO4.
1. When putting up an AGM/LiFePO4 for short term storage .. it's best to start with a full charge. putting a LiFePO4 or any other li-on into long term storage covers a topic on it's own.
2. both AGM and LiFePO4 are low self discharge batteries. it's not unusual to see LiFePO4 hold a charge nicely for 1+ year. internal protection circuits if any can add to self discharge. AGM in good condition can easily hold a charge for 6+ months. all PB batteries including AGM like being close to full charge to avoid sulfation.
3. after charging AGM/LiFePO4 to full charge .. disconnect battery terminals (ground) to terminate parasitic drain if any.
4. every 6 months or so .. go back and charge back to full. for AGM that would be about 12.85v after sitting overnight .. for LiFePO4 that would be 14.6v immediately after charging to full .. then depending on internal electronics .. about 14.2v to 13.9v after sitting overnight for LiFePO4. it's OK to scrub surface charge by applying a small load if you don't have patience to wait overnight.
acceptable chargers:
trickle type chargers like battery tenders are not on my favorites list. but will work in a pinch .. so long as you understand time limitations. depending on AH size, it could take several days to reach full charge at say 500 milliamps. trickle chargers are NOT recommended for recovering AGM/LiFePO4 from dead. my recommendations when attempting to recover from dead is to charge at 1C. this will be covered in more details in an upcoming tutorial on recovering batteries from dead and/or extremely low voltage.
lots of choices for AGM/LiFePO4 .. most any 12v PB charger with enough amps (not trickle charger) will do .. make sure 12v charger in question doesn't have a desulfation mode which typically spikes voltages to 15.1v+ which could kill both AGM/LiFePO4.
for LiFePO4 if one has $$$ go with Optima LiFePO4 charger .. otherwise go with an old dumb 12v charger like say 10amp Schumacher, but make dead certain it puts out 14.4v and no more. these typically sell for $25 range. your bike's alternator is really just a dumb charger driven by your engine with voltage regulator limiting volts delivered.
ALL batteries will naturally self regulate amps/absorbtion rates as it reaches closer to full charge. but will not regulate voltage delivered. (note charging lithium cobalt cells is a topic to itself)
think water in a pipe: amp = flow ... voltage = pressure
voltage delivered determine force amps will be pushed into cells.
Last edited: 26 minutes ago
http://advrider.com/index.php?threads/motorcycle-batteries-agm-gel-wet-lithium-iron-phosphate-lifepo4.757934/page-124
- CW
How to put away a battery for the winter:
this is for folks with AGM and LiFePO4: all voltages need to be taken with a known to be correct meter.
for sloosh PB those will need some type of trickle charger which is NOT recommended for AGM/LiFePO4.
1. When putting up an AGM/LiFePO4 for short term storage .. it's best to start with a full charge. putting a LiFePO4 or any other li-on into long term storage covers a topic on it's own.
2. both AGM and LiFePO4 are low self discharge batteries. it's not unusual to see LiFePO4 hold a charge nicely for 1+ year. internal protection circuits if any can add to self discharge. AGM in good condition can easily hold a charge for 6+ months. all PB batteries including AGM like being close to full charge to avoid sulfation.
3. after charging AGM/LiFePO4 to full charge .. disconnect battery terminals (ground) to terminate parasitic drain if any.
4. every 6 months or so .. go back and charge back to full. for AGM that would be about 12.85v after sitting overnight .. for LiFePO4 that would be 14.6v immediately after charging to full .. then depending on internal electronics .. about 14.2v to 13.9v after sitting overnight for LiFePO4. it's OK to scrub surface charge by applying a small load if you don't have patience to wait overnight.
acceptable chargers:
trickle type chargers like battery tenders are not on my favorites list. but will work in a pinch .. so long as you understand time limitations. depending on AH size, it could take several days to reach full charge at say 500 milliamps. trickle chargers are NOT recommended for recovering AGM/LiFePO4 from dead. my recommendations when attempting to recover from dead is to charge at 1C. this will be covered in more details in an upcoming tutorial on recovering batteries from dead and/or extremely low voltage.
lots of choices for AGM/LiFePO4 .. most any 12v PB charger with enough amps (not trickle charger) will do .. make sure 12v charger in question doesn't have a desulfation mode which typically spikes voltages to 15.1v+ which could kill both AGM/LiFePO4.
for LiFePO4 if one has $$$ go with Optima LiFePO4 charger .. otherwise go with an old dumb 12v charger like say 10amp Schumacher, but make dead certain it puts out 14.4v and no more. these typically sell for $25 range. your bike's alternator is really just a dumb charger driven by your engine with voltage regulator limiting volts delivered.
ALL batteries will naturally self regulate amps/absorbtion rates as it reaches closer to full charge. but will not regulate voltage delivered. (note charging lithium cobalt cells is a topic to itself)
think water in a pipe: amp = flow ... voltage = pressure
voltage delivered determine force amps will be pushed into cells.
Last edited: 26 minutes ago