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Old 02-07-2019, 04:44 PM   #213 (permalink)
IamIan
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Quote:
Originally Posted by Ecky View Post
I believe cold increases the battery's resistance anyway?
Yes.

If they are anything like the performance curves for A123 style LiFePO4 cells .. the attached are graphs showing the effect of SoC and Temperature on a cell's effective ohms.

Even if (as a different brand) the curve is a little different than A123's , I would still suspect similar overall shape / trend.

Quote:
Originally Posted by Ecky View Post
None. The smallest 100A relay I could find had an active power draw of ~12w, and most of the nicer ones are ~20-30w. To me that's pretty unacceptable.
You could move away from mechanical relays , to solid state stuff instead.

Although the premade solid state such disconnects are a bit expensive .. they do show how significant of a drop solid state options give for the switch's power consumption rates.

Random example of such pre-made solid state (Mosfet) low voltage disconnect.

Amazon
Victron Spec pdf
$40 with S&H
Load = 65A continuous , 250A for 30sec
Self Consumption = 1.5mA on , 0.6mA off
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Ecky (02-07-2019), hayden55 (02-14-2019)