Can you "cycle" a lead acid battery?

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Last night, while waiting in a parking lot for a local armslist.com transaction, I turned the car off and was listening to the radio. Also had the HVAC fan turning. Also had the parking lights on. The other party was 30 minutes late. I found that after all of that, I had drained my battery enough to require a jump. So my wife came out and we jumped my car and drove home.

This morning, it seems that the battery turned the starter motor over with spirit and enthusiasm, and it seemed to start very quickly at lunch today as well. Is it possible that draining the battery and then re-charging it on a 15 minute drive home "added" (or at least restored) cranking amps to the battery? I hear of that on certain types of small electronics batteries, but was curious if that was possible on a lead acid starting battery.

Could all be in my head, though.
 
I had a junk battery like that. Would go flat quick, would charge up (enough to start with enthusiasm) quick.
 
As i understand it, lead-acid batteries really dislike being deep-discharged, so cycling them through a full discharge-recharge cycle is not recommended.
However, high current pulses are used to desulphate the plates, in cases where sulfate crystals form on the plates and thus decrease the surface area available for voltage generation. Perhaps your 15-minute drive was at high-enough current to loosen some crystals, and so rejuvenate the battery?
Regardless, I'd want to take the car for a longer drive, to ensure the battery is fully charged once again. I don't have numbers, but it feels like 15 minutes wouldn't be sufficient to fully recharge a battery that needed a jump.
 
Tjhey can cycle, but cycle life for lead acid is very low, especially the low impedance SLI type batteries used in cars.

Id recommend doing a proper topping and equalization charge with a proper charger that is thermally compensated, in order to properly top it back off. Alternators dont do it well/properly...
 
Sounds like it's time to start battery shopping! 30 mins of accessories shouldn't drain a battery to the point of requiring a jump, and lead acid batteries don't like being cycled like that.
 
Thanks. I don't know how "deep" it was discharged. It had enough oomph to turn the engine over, but just not QUITE fast enough for it to light. It would cough, but would never start. With the jump, it still turned over slowly, but it started. Today, the battery turns it over like a champion! Weird.

Will monitor it. It's a Duracell/East Penn 51R. 3 year free replacement warranty, prorated to 8 years I think. It's 2 years old this season.
 
Traditional car batteries have about 10 cycles in them before they will die.

They were never designed for accessory use when vehicle is off.

AGMs were designed to be resilient in this regard.
 
What you did is actually pretty harmful to a standard lead-acid battery. They do NOT like a quick charge after being deeply discharged. If one does get run flat enough to need a jump, and you have the option, the best thing to do is recharge it over many hours with a 2- to 4- amp trickle charger. Obviously you didn't have a choice here, and a healthy battery should have several "incidents" like that in its lifetime- but each episode of rapid re-charging from a deep discharge takes life off the battery.
 
Originally Posted By: TrevorS
Traditional car batteries have about 10 cycles in them before they will die.

They were never designed for accessory use when vehicle is off.

AGMs were designed to be resilient in this regard.


There are two types of flooded batteries. Starting and deep cycle. Starting should never be deep discharged. Deep cycle can tolerate it much better. This is more to do with boat batteries. You could always put a deep cycle in a car if you wanted to and it would fit and had enough CCA,
 
I understand that lead-acid batteries have only a finite number of deep discharge cycles. 10 cycles seems kind of low.
 
Replace the battery if older than 5 years and be sure... If it stays weak it does damage to other electrical components
Replace with a good battery with lots of cca's
 
As other have correctly pointed out you are rolling the dice with that battery, but you can stack the odds in your favor. If you want to restore as much life as you can back into that battery, you'll need to charge it properly with a battery charger. A slow, low-amperage charge for X hours will help immensely.

Relying on the vehicles charging system to "charge up" the battery is a bad idea. It will not charge the battery properly and driving around on a low battery is a great way to pop the alternator. You've been lucky, but foolish so far.
 
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automotive type wet batteries are designed with low impedance, shallow discharge cycles (less than 50%) with short duration (or "burst" if you like) of high current to turnover an engine, etc.

It's meant to be immediately recharged right after a discharge session (e.g. turnover an engine to start a car, etc.)

It's not meant to be deep discharged for it will cause damage including sulphation, etc. which cannot be removed by any means (other than being recycled for lead).

On the other hand:deep cycling wet batteries (lead acid) oftentimes have different plate structures and thicker, if not more robust plates..weigh in at least 3x more to that than regular automotive batteries for the same kind of discharge capabilities.

They tend to cost more also: (e.g. Trojan wet cell deep cycle lighthouse batteries costs (example: trojan 6V 370A/hr battery costs around 400bux each + delivery)...these are the kind of batteries with different discharge characteristics that would allow them to discharge (still shallow discharge, meaning less than 50% whenever possible) deeper and recovers through proper recharging/cycling and lasts longer also.

My wifey's camry battery only lasted 3.5yrs before it became week (replaced past november,13) due to frequent unintended discharging (left dome lights/trunk light on, etc.)

Q.
 
All hail the mighty alternator and its nearly instant battery charging proclivities.

Or so it seems.


After a jumpstart is required, relying solely on the alternator for a full recharge the jumped battery is unwise in the extreme. The last 20% will take hours and hours no matter what the charging source is. Returning the battery back to 80% might not take all that long depending on the vehicle's capabilities and actual remaining capacity in the battery. It is best done by putting a grid powered charger on the battery that can provide initially, about 10% of the amp hour capacity.

But some grid powered chargers might goto too high a voltage, which might possible damage sensitive electronics, so the battery should be disconnected from vehicle, but that can also cause issues depending on the vehicle. Just something to be aware of.

There are actually 3 types of Flooded lead acid batteries. Starting/lighting/ignition batteries, Marine/RV/Dualpurpose batteries, and then the venerable expensive, hard to actually acquire, true 12v deep cycle battery.

The Dual purpose marine battery is a starting battery which is more tolerant of deeper discharges. It has slightly lower CCA ratings. It loves all the marketing labels thrown on the side of it. I suspect many marine batteries are just starting batteries with a 15$ sticker on them, and some threaded posts in addition to the normal automotive studs.

As far as the OP's vehicle seeming to start perkier after needing a jump and then a 15 minute drive home, There is no way the battery got fully recharged in 15 minutes.

Now here is my personal opinion from living off battery power for longer than I like to admit. Much of the traditional battery recharging methods handed down by grandpa, mainly the low and slow trickle charge being best, are false.

Many/most battery manufacturers have a minimum charging current recommendation, at least for their deep cycle flooded batteries, and none of them say feed them as little current as possible for as long as possible to recharge. Generally the recommendation falls from 10 to 20% of the amp hour capacity measured in the 20 hr rate.

Meaning feed a depleted 100 amp hour battery a minimum of 10 amps initially for that 10% rate.

I have one battery right now, Albeit a true deep cycle battery, which wants that 10% rate, however when discharged, and I allow my alternator to feed it, the battery will initially take a 50% rate, and higher, if the rpm's are there to provide it. This battery being blasted, even briefly, with a much higher than recommended charging rate might shorten its life, but it holds higher voltages through the next discharge cycle, compared to the solar's low and slow to full charge over longer periods.

So I believe it is possible as one other poster indicated that this battery was partially sulfated before needing the jumpstart. The Sulfates blocking electon transfer and making the battery seem a bit dopey.

After the jumpstart, the battery was thirsty for amps and took everything it could which the alternator could provide for those 15 minutes, in which the battery was also physically agitated by driving motions. This amp blast and physical agitation knocked loose the hardened sulfate on the plates allowing it to settle on the bottom of the cells, exposing fresh plate material to transfer electrons and even being less than fully charged the next day, seemed perkier than the day before.

Even though 15 minutes of driving was nowhere near enough to fully charge this battery, the surfaces of the plates were less obstructed by hardened sulfates and so it now seems Zippier.

That sulfated plate material which got knocked off the plates is now resting on the bottom of the cells. That material was part of the batteries electrical capacity, so while the battery just lost capacity, it has increased the surface area on the plates returning a higher CCA rating and a perceived zippier starting experience.

The battery might last for years longer, if it is put on a grid powered charger, or it could die tomorrow if so much shedded plate material fell off that the cell might short out. In general Starting batteries are very intolerant of deeper discharges and a deep discharge halfway through its lifespan will kill it in short time. But if it was promptly and fully recharged at a reasonable rate, it might not have lost much capacity at all.

It is the slow discharge to dead, and sitting there dead for a while which really is the battery killer.
All lead acid batteries want to live their lives as close to 100% fully charged as possible. The battery owner who is aware of this, and that the alternator is not a magical near instant battery charger, and employs other methods to return a battery to 100%, will enjoy long battery life, probably. Some people never discharge the battery much at all and the vehicle's charging system keeps the battery above 95% and enjoy long life spans.

Note AGM batteries are different, as even if designed as a deep cycle battery, they can still provide huge CCA ratings. When deeply cycled, AGM batteries like Odyssey in particular, want a large current to recharge. A hundred amp hour battery initially wants 40 amps until 14.7 volts is reached. 14.7 volts it then to be held for 4 hours as the current required to hold 14.7 tapers down low.

Without meeting this recommendation, A deeply cycled Odyssey AGM will never reach full energy density, Despite that highly rated chromed alternator under the hood and the chest thumping confidence of the owner of said chromed alternator. According to an Odyssey tech I spoke at length with, it would require 2 more cycles, being drawn below 50%, then recharged at that 40% rate and 14.7 held for 4 hours, before full capacity was restored. Even without this proper recharge regimen on an Odyssey, it will still likely outperform a flooded battery, and for nearly 3x the price, it better.

I feel this is also true of flooded lead acid batteries to a much lesser degree. Without any backing data or engineers on my side, I feel a deeper discharge and a prompt and full recharge at a 10 to 20% rate is like a slap across the face followed by a cup of coffee to a battery which got bored of life in the 75 to 85% charged zone.

The thing is the slap and the cup of coffee might send a weak battery with no constitution to the recycler. The thinner the plates, the more likely that this aged battery will get all petulant at this treatment and quit.

To the OP, I'd recommend carrying jumper cables, and acquiring an Automatic battery charger in the 6 to 10 amp range, and letting it do its thing over night. If you ever do deplete the battery again, make sure to use the battery charger again promptly, and not rely on the alternator for a true full charge, unless you are driving for 500 miles.
 
Originally Posted By: wrcsixeight
All hail the mighty alternator and its nearly instant battery charging proclivities.

A deeply cycled Odyssey AGM will never reach full energy density, Despite that highly rated chromed alternator under the hood and the chest thumping confidence of the owner of said chromed alternator.


Awesome! You are a true wordsmith. I am not being sarcastic.
 
Originally Posted By: Kestas
I understand that lead-acid batteries have only a finite number of deep discharge cycles. 10 cycles seems kind of low.


given impedance growth and surface chemistry changes associated with calendar life ageing, its probably pretty accurate in reality for a typical lead acid.

In the lab they can surely do more, but in a vehicle?
 
to wrcsixeight's long commentary- good stuff, but there is some evidence in the surface science and SEM/TEM community that a fast charge and/or a pulsed charge for a while can help rejuvenate the surface lead in a different way than a typical charge. Of course you have to balance gassing which will generally occur immediately from a flooded cell and at about 3C rate from an AGM. So you dont want to do it forever, but the stresses due to a faster charge can be beneficial actually for a short time.

The problem is that the alternator isnt current limited per se, thus will slam too much in, but in the wrong way. After a little higher rate charging, a proper CC/CV topping and equalization charge at about C/4-C/10, depending upon the battery, is optimal generally. Anything faster and you really can only get in about 80% of the charge anyway, and youre risking gassing and electrolyte loss.

I HIGHLY recommend that the OP put a proper charger onto the battery (one that does the right profile, not that HF junk) and let it charge overnight or as long as possible.
 
I will put the battery on a charger this weekend. I have a plug-in Sears Craftsman battery charger, the old school metal kind.

Maybe this battery was weak from jump street, so to speak. I've done this for years (run accessories for relatively short periods of time) and have never had to replace a battery before I felt it was due and I've never had to replace an alternator in my life. Maybe I've just been lucky.
 
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