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Old 03-07-2012, 08:18 PM   #135
_cy_ OP
Beastly Adventurer
 
Joined: Sep 2011
Location: Tulsa, Oklahoma
Oddometer: 5,062
Let's explore the wealth of available data for AGM battery's cold weather performance. which would be battery of choice over Gel and wet PB before LIFePO4 came along. Peukert's law is also explained in detail link below.

note at 15f degree temp losses are about 7%. fortunately Motorcycles don't have to worry about starting at much below 15f. couldn't say the same for Snowmobiles.

in terms of cold weather performance for Motorcycles. AGM sets the bar to beat. it's also 10+ lb heavier than LiFePO4 for R80G/S.

Temperature Losses

Generally speaking, as a molecule is reduced in temperature, the less active atomically it becomes. This affects many exothermic (heat inducing) reactions including the power generated by lead acid batteries. In cold Colorado winters, be they AGM, GEL or flooded in composition, all batteries efficiency are negatively affected. The graph shows the negative correlation between temperature and battery capacity in an AGM battery. Notice how a 100 amp/hour battery at 90 F has only 55% of that capacity at 4 F and 43% capacity at -22.

http://www.bdbatteries.com/peukert.php

_cy_ screwed with this post 03-07-2012 at 08:28 PM
_cy_ is offline   Reply With Quote