Thread: Battery info
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Old 12-29-2020, 04:16 PM   #44
JohnnieB
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Default Re: Battery info

Quote:
Originally Posted by badandyturbo View Post
So according to Crown my 50% SOC is 48.5v. That being said when should you measure the reading? While driving? After stopping? After resting 5 minutes?
For estimating SoC, the batteries need to be At-Rest. That is about 12 hours after the charger shuts off, or about 1 hour after the cart stops moving.

The batteries acquire a surface charge while charging that contains almost no stored energy and must be bled off via self discharge to get an accurate SoC estimate. The opposite is true when amps are drawn from the battery, but voltage recovery is quicker than self discharge, so only about an hour is needed.

When out and about and wanting to know when to head back to the charger, I use 10 or 15 minutes of rest time, knowing the SoC will be underestimated by about 4% or 2% respectively. With 5 minutes of rest the error will by about 5% low, or so.

Attached is a recovery time chart I made for some old Trojan T-105 batteries. Recover time for Crown batteries will be different.

Here's a SoC chart for Crown lead-acid, wet-cell, deep-cycle batteries.
Attached Images
File Type: jpg Voltage Increase after load.jpg (100.4 KB, 0 views)
File Type: jpg Crown SoC chart.jpg (208.1 KB, 0 views)
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