Lead Crystal Batteries

[jpaulstephens]

Thanks for your response. I am aware that mix -match batteries is a recipe for problems. However, this was a one-off interim measure till i could find a decent full replacement.

As regards the charge cycle you describe i was fully aware that we shouldnt drop below 50% charge, but we never get that low before the voltage reaches 12.05v. So we never drop below 75% charge, and now not below 90%. I usually recharge to 100% using the generator. I begin to suspect that the Xantrex charge information is in some way wrong.

All ideas welcome��

[StuM]

Originally Posted by jpaulstephens

Thanks for your response. I am aware that mix -match batteries is a recipe for problems. However, this was a one-off interim measure till i could find a decent full replacement.

As regards the charge cycle you describe i was fully aware that we shouldnt drop below 50% charge, but we never get that low before the voltage reaches 12.05v. So we never drop below 75% charge, and now not below 90%. I usually recharge to 100% using the generator. I begin to suspect that the Xantrex charge information is in some way wrong.

All ideas welcome��

I'm sure it is wrong! If your batteries are down at 12.05V, thre is no way you are at even 50% SOC, let alone 90%. It looks as though your battery bank's actual capacity is down to only 100Ah or less. If your Xantrexl is "coulomb counting", and it has been told that you have several hundred Ah of capacity, the displayed SOC% will be completely wrong.

[jpaulstephens]

Thanks. I set up 360Ah into the Xantrex in Darwin based upon 4x90Ah batteries in good condition.

[daletournier]

Ignore your amp counter and believe your volt meter. 12.05v is just to low on a regular basis, with respect this seems to be a management problem.

[ranger58sb]

Originally Posted by jpaulstephens

As regards the charge cycle you describe i was fully aware that we shouldnt drop below 50% charge, but we never get that low before the voltage reaches 12.05v. So we never drop below 75% charge, and now not below 90%. I usually recharge to 100% using the generator. I begin to suspect that the Xantrex charge information is in some way wrong.

Xantrex is likely wrong. 12.05V is too low to start recharging.

For one of our 12V battery banks, 12.18 open circuit voltage would be 50% DOD (50% SOC), and that'd be a good target minimum point for us to start recharging.

(12.06V would be 40% SOC, 60% DOD).

Even better, for our bank, would be beginning recharging at at 12.48V (75% SOC, 25% DOD) as often as possible.

-Chris

[john61ct]

This thread is about the performance of Lead Crystal chemistry batteries, and there seems to be very little progress on verifying Betta's claims.

So the answer for now AFAIC would be to avoid LC and purchase from a known-good manufacturer.

Originally Posted by jpaulstephens

I would also welcome any insights into my poor battery performance. I am finding it hard to maintain battery life on my circumnavigation. We draw 5-15 amps from a 500ah bank of supposedly deep cycle sealed lead acid batteries replaced 7months ago in Panama.

I would suggest you should start a new properly titled thread on this topic and you will get more and better feedback.

Summarize your experience and give as much detail as possible in that first post.

[rwidman]

Originally Posted by sailinglegend

..........This is where you show your ignorance. ...........

That's a bit more rude than it needs to be, don't you think?

[mitiempo]

Originally Posted by jpaulstephens

........ I usually recharge to 100% using the generator. I begin to suspect that the Xantrex charge information is in some way wrong.

All ideas welcome��

I very much doubt you fully charge with a generator. It would take 6 to 8 hours to do this. Batteries are fully charged when they are accepting about .5% of capacity at absorption voltage - 14.4 or whatever the setting is. They do not charge appreciably at float voltage.

I agree the Xantrex is wrong.

[GTom]

Originally Posted by mitiempo

It would take 6 to 8 hours to do this.

From SOC = 70% too?

[john61ct]

The batts current acceptance is still pretty high from 70% to 80-85%, but drops way down over the next 3-5 hours to get to 100% Full as defined by endAmps, no matter how big the charge source.

FLA slower than AGM, but applies to all lead.

This is why you need some solar for that long tail to get to full, just silly to try to do so with dino juice sources alone.

LFP has no such problem.

[donradcliffe]

Originally Posted by jpaulstephens

I see this thread has gone quiet for 4 years. I am sailing to South Africa in need of new batteries and see that Deltco offer a Lead Crystal product along with AGMs and Gel batteries. Can anyone update me on their experiences with lead crystal batteries at sea?

I would also welcome any insights into my poor battery performance. I am finding it hard to maintain battery life on my circumnavigation. We draw 5-15 amps from a 500ah bank of supposedly deep cycle sealed lead acid batteries replaced 7months ago in Panama.

At the outset they discharge to 12v after drawing 75% of capacity. Now we have to charge at only 85% capacity on reaching 12v. The batteries are charged by solar panel and wind generator that deliver more than the load in 30 knots and sunshine, but at night I now need to turn the generator on every three hours.

Peukerts Law clearly involved here, but i am still surprised that we don't maintain 12v down to about 50% of capacity. Deltco is the first manufacturer I have found which provides detailed charts and performance specs.

I agree that the Lead Crystal guys have slunk off into the sunset, to be followed by the firefly guys--so much the better. Lets work on your problems.

Firstly, there are people who sell sealed lead acid car batteries, AKA zero maintenance, AKA calcium batteries. These are the absolute worst batteries for a boat, as they have a VERY low cycle life and are vulnerable both to to overcharging and undercharging. Any 'deep cycle' language for these batteries is just marketing puffery. You would have been far better off getting the golf cart (GC) 6v technology. LIFE batteries are the real deal, but based on your state of technical knowledge, they are not for you.

Secondly, the Xantrex battery monitor state of charge is way off, and you are undercharging what's left of your batteries. A 400 amp hour bank is not near fully charged until it accepts less than 1%, or 4 amps at 14.5 volts. If your smart charger is timing out and cutting the charge voltage back to float when a 400 amp hour battery bank is still accepting 10-15 amps, its time to reset the charger, easily done by turning the charger off and on if it is connected to a genset, or turning the engine ignition switch off and on if a smart regulated alternator is charging.

Note that if you ever get your batteries fully charged, the Xantrex monitor will reset its SOC monitor.

PS Your boat sounds like an energy hog if you use 45 Ahrs in 3 hours. either put it on a diet or double the size of your electrical system.

[john61ct]

Originally Posted by donradcliffe

to be followed by the firefly guys.

WTF is that supposed to mean?

[mitiempo]

Originally Posted by GTom

From SOC = 70% too?

Charging to about 85% SOC will be as quick as the charge source and battery acceptance allows. For flooded batteries about .25C. The last 15% of charge is controlled by the batteries increasing resistance. As the resistance increases the battery bank accepts less and less current. This assumes that the charge source stays at absorption voltage long enough to achieve a full charge. Many do not, switching to float voltage way too soon. At a float voltage that occurs too soon charging to full, if it is attained, could take many hours longer.

A battery is considered fully charged when it is accepting about .5% of its capacity at absorption voltage, not at float voltage.

This link documents the charging time to full of an Agm battery from 50% SOC. It took 5 hours and 30 minutes.

How Fast Can an AGM Battery Be Charged..? Photo Gallery by Compass Marine How To at pbase.com

Also if the battery bank was at 12.05 volts at the beginning of charging it was somewhat below 50% SOC to begin with.

[john61ct]

And once permanently damaged by PSOC abuse, the bank's charge acceptance behaviour goes out the window.

[GTom]

Originally Posted by john61ct

And once permanently damaged by PSOC abuse, the bank's charge acceptance behaviour goes out the window.

Back to the "lead crystal" topic, they claim to be more resistant to PSOC among some other recent developments. A good solar panel seems to be a must for a lead battery...