“Exercising” house deep cycle batteries

[Joe Monaco]

Just installed new start and house batteries. I read somewhere that it’s a good idea to draw down the deep cycle batteries and then recharge them. Is there a preferred way to do this? Is this something most folks do or is it not that important?

Thanks!

Topic

[Rob Schepis]

Scott Lambert wrote:

I would recommend fitting one, even though they are not cheap.

Thanks for the input Scott. Yes a “monitor” is pricey and adds the other features Scott mentions but a simple “meter” is cheap and easy and gives you that one most important pc of info – accurate voltage at the terminals.

The DVM:
https://www.sbmar.com/product/smx-digital-dc-voltage-monitor/

The Article;
https://www.sbmar.com/articles/installing-digital-volt-meters-dvm-boat/

[Scott Lambert]

Battery Monitor

I fitted a battery monitor when I replaced my house batteries. Like Tony says new batteries are a big investment and I have found the monitor extremely useful. I always know how many Amp hours used, what the charge/discharge rate is and what the battery voltage is. I would recommend fitting one, even though they are not cheap.

[Rob Schepis]

Joe, maybe you are thinking of the fact that the efficiency or performance of the battery will slightly improve after the first dozen or two discharge/recharge cycles? This is not something that you really need to focus on or try and “take control of” in the form of intentional discharging/recharging. The house battery (or bank) should be sized with more than enough reserve that your depth of discharge is not significant (~20%) and any slight performance improvement after initial “break in” or whatever you wish to call it is nothing of any real use or measurable difference anyway.

Keep the battery state of charge up, check/maintain the water level, refrain from deep discharges, and recharge promptly after discharge. The battery that has shallow discharge cycles can handle many more cycles in it’s life than a battery that has deep discharge cycles.

[Tony Athens]

I think you are getting confused with the new tech (or maybe old tech now) batteries used in cordless drills, etc that had a memory………………..

Batteries like you have have a finite amount of discharge cycles before they go poo-poo.. I’d say just the opposite– Put them on charge and get them up to spec based on the temp of the battery case and battery specs supplied from the manufacturer.. Voltage is measured at the battery terminals, not thru the DC panel if you really want to do it right.

A good write on this this by Rob Schepis ( do a search) . New batteries are a big investment and you should always know exactly what there state of charge is at the dock or when running.

Tony

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