Author Topic: What do you guys use to test SLA batteries for capacitance?  (Read 636 times)

Offline kid_couteau

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Hi All

What can you use to see how far along your batteries are to needing replacing?

Thank you
Kid

Offline FreeLancer

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Re: What do you guys use to test SLA batteries for capacitance?
« Reply #1 on: June 26, 2018, 05:19:29 PM »
I use the West Mountain Radio CBA IV to test all my batteries.

Offline Carl

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Re: What do you guys use to test SLA batteries for capacitance?
« Reply #2 on: June 27, 2018, 10:27:18 AM »
  I also use the West Mountain CBA for testing though a low budget method does exist.... I us 50 watt,12 volt light bulbs made for RV use and they require 4 Amps (for 50 watts) per bulb and can serve as a load test ,over a time period ...to provide a near continuous load on the battery while a Voltmeter can be checked from time to time to get a good idea of battery capacity. For larger batteries I often use 3 or more bulbs OR I just use a medium size inverter to power a 120 volt lamp for 150,250,500 watts of test capacity and the test,though not an exact science ....is good enough for my use.

Offline fratermus

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Re: What do you guys use to test SLA batteries for capacitance?
« Reply #3 on: July 07, 2018, 06:47:03 PM »
I think autocorrect changed capacity to capacitance.

What can you use to see how far along your batteries are to needing replacing?

Same way marine professionals do: 

remove from loads
install coloumeter (Ah counter, as little as $15 for our purposes)
drain at C/20 rate
stop at 10.5V
note the Ah on the coloumeter
recharge battery fully immediately

It's not just low-budget, it's the way the battery manufacturers rate the batteries.


Rule of thumb is that lead-chemistry batteries are replaced when their actual capacityAs long as Ah provided >= 80% of intial rating the batt has some life in it.   



Slower than the $150