Interesting statements considering the yellow has similar internal resistance and therefore should crank the same. (I'm looking at a yellow .0025mR spec versus the .003mR for the red, but they may be different capacities).
And the yellow may have higher terminal voltages (for reasons unknown).
But their internal resistances are for fully charged batteries (of course!) and can't be used for
real recharge current data. (Internal resistance increases with increasing discharge level. Just as well, otherwise many flat batteries would explode (not really...) or wreck far more alternators!)
And charging limits are the same, ie, 10A unless under ~50C when no current limit applies.
But crankers are different to deep cycle by merit of construction - ie, for the same
size (capacity?), high-current crankers have more thinner plates and hence more "current area" whereas deep-cycles have fewer but thicker plates to handle the greater discharge depth without as much plate damage.
And other batteries fall somewhere between the two high-current and high discharge-depth constructions.
And of course a big enough deep-cycle can supply adequate cranking capacity without significant damage. Conversely a big enough cranker can deliver a smaller deep-cycle's long discharge AH capacity (but still remaining within low %age
cranker discharge depth limits).
Though the above is almost common-sense (once you realise it), I am often surprised at some battery discussions. People may discuss the same battery but with its 2 different specs for differing applications. One simple case involved an argument between a 7AH C-20 and a 4.2AH C-1 rated battery for the same application, yet they were the SAME battery!
I thought audio forums took the prize, but others are well in the running too - like the authoritative or respected dude that was pooing the efficiency of using a battery by testing what it took to replace the same charge it delivered - but at 12.7V! (IE - he recharged at 12.7V since that's what the battery was. Do not pass Go. Don not collect any money.)
And they are often full of the same "must match batteries when in parallel" for systems that have auto-isolators (ie, only paralleled when charging or required).
But some audio forums probably take the lead
all things considered. By that I mean combining all their snippets into the overall system.
Some readers may have read threads hereon by someone also on a certain south-east stateside audio forum. There were statements like housing batteries in the engine compartment for greater capacity due to the increase temperature (they must have at least started with lots of money...).
There was also a rule like 100AH per kW of audio. I could only find the first post with that statement, but never found its source or what it's based on. I suspect it's someone's version of the oft used
100A per kW (for 12V systems).
I suspect too that a certain "Farads per Amp" rule is likewise a twisted application of another general power rule of 5-10uF per Amp or 10,000uF per Amp depending on how you engineer it. I'm waiting for the day that someone quotes a source or basis, and thereby probably declare that all this cap stuff it for a certain voltage dip after a mere 10mSecs. Whilst I know that that short time may have some
possible validity compared to batteries, I suspect most others will not know that connection. (Sorry for the double
may &
possible, but the latter may have validity wrt to one "theoretical" aspect of battery behavior, but I suspect it ignores another practical and real aspect.)
However that short time blows away any arguments for caps with burps lasting more than a fraction of a second, and then the battery continues and wins hands down (yes, even a $15 1.2AH).
Despite the above "general" rule I mentioned for 10,000uF aka 10mF per Amp, I know that some "quality" amps have 1mF per Watt of output, but that's a SMPS level - not the raw DC input level. (But that's where to add extra capacitance - NOT at the DC input level!! Not that money spenders are told that, or provided that option (though I understand why).)
Some know my views on how big amp design is totally flawed anyhow. IMO it's so stupid having the PSU in the rear-mounted amp instead of placing the PSU near the alternator and main battery and thereby distributing at least a ten-fold decrease in current to the amp(s) depending on local Regulations and their interpretation.
But there is so much money still to be spent on the current architecture (good pun eh?) that it may be a while before the split occurs. Of course multi-battery audio installations probably prefer the current method, and the long proposed conversion to 42V vehicle systems make the split system less attractive.
Geez, I kinda digressed, Again.
Did I mention the local SPL competition I attended? (No - only about disconnecting caps for higher peak SPLs?).
I noted that all the vehicles except for one used wet audio-battery banks. And no - the AGM did not win.
And I barely noted any caps. Mind you even the AGM vehicle had more than enough AGMs to not require that (for AGM potection; there were about 10 or more AGMs).
I've been meaning to go back to the store that hosted the event and discuss the issue. Maybe one day... Maybe one day I'll also mount my single speaker and beat the lot of them LOL! But why add to my already jeopardised status?
But my point is that maybe the locals agree that caps decrease the peak SPL. That may also account for their use of wet cells.
Anyhow this reply started with aspects of Optima battery ratings. I guess the recent posts have resurfaced some old discussions.
BTW - that "SE-audio" member recently reappeared to discuss capacitors. I suspect he had some new found formal education that spurred him. Unfortunately he lost sight of - or failed to understand - some simple basics about when capacitors charge etc. It wasn't long before he got into formulae etc which were at that stage far from relevant. In some ways that reflects some common forum discussions - too little knowledge, or too new and specific detailed knowledge that has yet to mature.
[When I consider what I've just written, I realise the multitude of experience albeit "electrical" whether it be batteries, or the tiny (if any) capacitance required for high-frequency power conversion (ie, SMPS). Some of us know that an inductor complements a capacitor, yet rarely is inductance discussed. (Ah - that might be the next revolution - high inductance oxygen free cable!).]
And FYI - a great source for battery info that I oft recommend is Bill Darden's
batteryfaq.org.
It's usually revised every few months (albethey minor - the basics don't change much), and now the downloadable
Battery.Zip is listed on the home page rather than its old buried location in chapter 19.
I can't recall if Bill goes much into some of the AGM-dislikes that I have mentioned though I suspect it's
readable between the lines as so much of battery detail is (ie, once you understand it, you realise something is covered in his writing), but he certainly did IMO palm-off aspects of paralleled batteries to elsewhere (clever Bill!!), though IMO that too is contained in his writings.
Maybe you suffered all the above for that link. Or did you just jump to it LOL?
And BTW again, great that your red top has lasted. It should last several more years.
I remember when I considered 3 years a good life for
my wet batteries. But with better battery technology, and my move to improved vehicle electricals (especially the relatively recent conversion to all-in-one alternator-regulators, and maybe too the in-dash digital voltmeter), I now expect at least six years even with my abusive behavior.