breaking in new batteries ?

[Stephen K]

I have learned so much from this forum, but I still consider myself a rookie at electrical stuff. I recently replaced my 2- 4D house bank and cleaned up the wiring by tracing and labeling all wires, adding bus bars and fuses. Now I read about breaking in these new batteries on this site...and from the guidance at Ample Power.

Intuitively it makes sense, but I admit that I am apprehensive about draining these new batteries down to about 10.5 volts over a 24 hour period.....isn't that the level of a dead battery?

Can anybody give me a little boost of courage or some more input to do this? By the way, I don't have a battery monitor yet, but plan on adding a Victron soon.

 

[Maine Sail]

I have learned so much from this forum, but I still consider myself a rookie at electrical stuff. I recently replaced my 2- 4D house bank and cleaned up the wiring by tracing and labeling all wires, adding bus bars and fuses. Now I read about breaking in these new batteries on this site...and from the guidance at Ample Power.

Intuitively it makes sense, but I admit that I am apprehensive about draining these new batteries down to about 10.5 volts over a 24 hour period.....isn't that the level of a dead battery?

Can anybody give me a little boost of courage or some more input to do this? By the way, I don't have a battery monitor yet, but plan on adding a Victron soon.

You don't need to drain them dead just cycle them to 50% a few times, and re-charge and your Ah capacity will begin to awaken... Takes a number of cycles before you get the full capacity..

 

[caguy]

Does that explain why the batteries (Group 27) I just bought from Costco only charge up to 12.4 v. I thought it was my charger. What do you recommend dropping the voltage to? I switched them out from the 24s.

 

[Maine Sail]

Does that explain why the batteries (Group 27) I just bought from Costco only charge up to 12.4 v. I thought it was my charger. What do you recommend dropping the voltage to? I switched them out from the 24s.

No it does not. 12.4V is about 70% state of charge if it is a 24 hour resting voltage reading. They should still have a 24 hour resting voltage of about 12.7 - 12.73 if wet cells to be 100% full. They should show this whether or not they are broken in..

What charger, brand model etc. and how long are you leaving it on?

 

[Bob J.]

Now I read about breaking in these new batteries on this site...and from the guidance at Ample Power.

I have never, ever heard of that.
Guess you can learn something new everyday!

 

[Stu Jackson]

What's so hard?

Breaking in New Wet Cell Batteries: http://c34.org/bbs/index.php/topic,6353.0.html

 

[Stephen K]

You don't need to drain them dead just cycle them to 50% a few times, and re-charge and your Ah capacity will begin to awaken... Takes a number of cycles before you get the full capacity..

Thanks Maine. Since I don't have a battery monitor, would you suggest me going to someting around 12.0 to 12.2 reding on a digital multimeter?

 

[rardiH36]

Does that explain why the batteries (Group 27) I just bought from Costco only charge up to 12.4 v. I thought it was my charger. What do you recommend dropping the voltage to? I switched them out from the 24s.

Mainsail already responded expertly as usual.

But just for additional reference, in Feb 2011 I also bought two group 27 marine batteries from Costco. ($69 each, not bad.) I'm not at my boat now to look, but I believe that they were dual duty type. I brought along my voltmeter to Costco and also sorted through the rack to find the latest stock date batteries. (No easy task considering how much the things weigh!) Both batteries from memory were 12.78V ex the rack.

My "charger" for both batteries is one 20 watt solar panel wired into a "duo" type charge controller that keeps the charging of each battery separate. Occasionally I disconnect the charger before leaving in the afternoon. And then check the voltages the next day. Always 12.8V+. I still haven't added any distilled H2O when I check about once per month.

The batteries have never been depleted anywhere near stress levels. I just day-sail with the GPS, autopilot and instruments sipping the voltage; and listen to the stereo when at my berth. For the over-nighter, the draw is primarily the LED cabin lights. Real ice and ice packs in a cooler still work OK for a day or two.

Guess it's possible that you have a different manufacturer at your Costco and also its 15 months on for Costco to have switched suppliers.

 

[caguy]

I think it must have been the charger. I pickup a new one at Pep Boys and the batteries went to 100% after a couple of hours. The extra amp hours will be nice. They fit into the battery well afer putting the old battery covers on the bottom raising the floor 2". I should be able to last 4-5 days on the hook.

 

[Maine Sail]

Thanks Maine. Since I don't have a battery monitor, would you suggest me going to someting around 12.0 to 12.2 reding on a digital multimeter?

The only way an open circuit voltage test works well, for an accurate SOC reading, is to let the batteries sit for 12-24 hours, no charge, no loads.. This does not work very well on a boat you are using.