Guest MegaloManiac Posted December 25, 2006 Report Share Posted December 25, 2006 Ok I was on another forum and I was getting some advice on batteries and this guy had a nice lil informative comment so here is the conversation(minor alteration) orginal thread: http://www.mp3car.com/vbulletin/showthread.php?t=92322 (starts on pg 3) Megalo: my iraggi has a 115a at idle and 200a on a higher rpm. I had a choice to get the 65a on idle but i decided to step my game up a bit with the higher current on idle, best choice i made. my lights will dim only at the lower notes, but i can solve the problem with an extra battery, right now i only have a yellow top under the hood...yes i am pulling quite a bit of power.(around 1200watts from the NINe1 and 170watts for the frontstage, plus around 60-80watts for the carputer...and etc for various other things like headlights and ac.) a 2nd battery should help MY situation. GoHybrid: I think the thing to do in megalorese15"'s case would be to figure out WHY he is pulling more than 115A at idle, and why that power isn't being supplemented properly. That's an awful lot of power. But here's a consideration: his battery is at fault. If all he has is a yellow top then that may be the problem right there. Yellow top batteries are deep cycle batteries. That means they are mean to sustain a lower current draw for an extended period of time, particularly without the application of a charger (hence "deep" cycle). If he is exceeding his alternator's output capacity and is counting on more power in a hurry from his battery, then a yellow top is the wrong place to look. Red tops are FAR more appropriate for the kind of multipurpose applications we subject our starter batteries to. The point is that Red tops are constructed in such a way that they can supply INSANE amounts of current at 0 degrees in an instant for say... starting a cold motor? As it turns out, this is exactly what he would need for his situation. Sudden high current draw = use the correct battery. If that didn't solve the problem itself, then what he ought to do next is consider an appropriately sized capacitor. Their quick charge/discharge times far surpass that of any battery and frankly, that is his dimming problem. Not enough amperage the instant he needs it. Granted, an additional battery connected in parallel will have the same effect as using the right battery to begin with, but then he can further complicate matters by having to make sure that he doesn't exacerbate the problem by suddenly having to charge TWO deep cycle batteries at 15+ amps a piece for the entire duration of his journey. In my opinion, he spent all that money on a fine alternator and he ought to consider both alternatives and use that power efficiently rather than just band-aiding the problem with more batteries. i might also add that the correct use of yellow tops would be to power a sound system for competition or while the car is off. In this case you would use as many yellow tops in parallel as you needed to be able to supply the instant current demands, plus as many as you need to be able to achieve the run time desired. Bear in mind though, charging many batteries like that requires sophisticated chargers and above all... lots and LOTS of current. Megalo: I did and still compete in spl compettions now and then. The burps drain a lot of power. but I comepeted USACi outlaw style. so alty did take a large role for the good. I thought about investing in a redtop for under the hood and have the yellow in the trunk linked together in paralel. But don't know too much about what batteries to use. Here's what do I know. the yellow tops are deep cycle and are usually meant for the "accessory" load. the deep cycle part is the bateery can be drained and recharged several times without damgin battery life. I'm not too sure what the marine "bluetop" is used for besides boats, but I've seen ppl use them in cars. now I did thought about using a Kinetik 2400 for a trunk battery since it has a current capacity than a g31 yellow top. advice will be appreciated. but please I am very hard headed about caps so don't mention them. I might consider a batcap. GoHybrid: okay, speaking strictly batteries now: With regards to battery construction there are some subtle differences between a deep-cycle and starter battery that significantly affect their performance. The basic reaction is between the electrolyte and the lead plates that comprise each cell of the battery. One of the effects of this reaction is a degradation of the lead plates, particularly following a deep discharge (80%) cycle. This is sometimes referred to as sulfation. A starter battery has many thin plates, sometimes with hole patterns in them to increase the surface area of the plates. The more lead plate in contact with acid, the more reactions you get, and thus more current. This means that you can have a smaller battery give more power very quickly. Because the plates are so thin though, the effects of that degradation are more pronounced and can quickly diminish the capacity of the battery to perform. Since your alternator can supply adequate charging current, this should not be a problem since you can start reversing that reaction the second it occurs and can leave the battery in a high state of charge. Just don't run your stereo with the engine off. Deep cycle batteries use much thicker, and therefore heavier plates. As a result a battery of the same size cannot supply as much current. The thickness of the plates however allows this kind of battery to tolerate deep discharges better than starter batteries. Bottom line... there's just more fresh lead there to work with. This makes the battery suitable for extended discharges with no replenishing current available. So if you wanted to run your system with the engine off, i'd find a way to isolate your starter battery (should be a red top) and link multiple yellow tops in parallel to be able to collectively supply the momentary loads your system creates. Alternatively, you CAN get a deep cycle battery with the same current delivery capacity as a starter battery, but it will likely not fit in your existing battery tray. So if you were one of those people who relocated their battery to the trunk and just used one or two group sizes UP, then you could use a deep cycle battery as your starter/standby battery as well. But that's more work... Here's another thing to remember: The harder you pull on a battery, the lower it's reserve capacity gets. A battery with a drain of 1 amp for 20 hours is going to hold out better than a 20 amp drain for 1 hour. So it is best to spread your load across as many batteries as is feasible for your application... assuming you don't care about adding 100lbs a piece to your car and want the best run time. if you're willing to consider a "batcap" then you're willing to consider a capacitor. That's what it is. search for "ultracapacitor" on wikipedia and you'll probably find some examples of these in the 500-2600 farad range. They even mention that this type of capacitor is used for temporary power during battery replacement.... so you can imagine how long these things can hold up to a load. The differences between this and a battery are vast, but the neat thing is that some of these higher rated units can fully charge in about 10 seconds. Show me a lead-acid battery that can charge that quickly and I'll show you a customer that needs about 6 pallets of them. Link to comment Share on other sites More sharing options...
S12X Posted December 25, 2006 Report Share Posted December 25, 2006 that is good info to have because for the longest time i always thought yellowtops were the way to go....but then i started hearing people talk about redtops and their advantages and it made sense new setup in the works Link to comment Share on other sites More sharing options...
ChevyBoy Posted December 25, 2006 Report Share Posted December 25, 2006 mir, whats his input on kinetik's? Link to comment Share on other sites More sharing options...
Guest MegaloManiac Posted December 25, 2006 Report Share Posted December 25, 2006 Its funny you said that, I just asked him about it heres what i wrote Megalo: good read do you mind if i post that post on other forums...of course i'll credit you also this comment Alternatively, you CAN get a deep cycle battery with the same current delivery capacity as a starter battery, but it will likely not fit in your existing battery tray. So if you were one of those people who relocated their battery to the trunk and just used one or two group sizes UP, then you could use a deep cycle battery as your starter/standby battery as well. But that's more work... Are you reffering to my kinetik battery statement? can you go in a bit more depth on this statement? how do you feel about using a kinetik under the hook and in the back? how well are they designed internally with the plates and all? Link to comment Share on other sites More sharing options...
ChevyBoy Posted December 25, 2006 Report Share Posted December 25, 2006 how does he feel about using a kinetik under the hook and in the back? how well are they designed internally with the plates and all? Link to comment Share on other sites More sharing options...
Guest MegaloManiac Posted December 25, 2006 Report Share Posted December 25, 2006 i'll edit my post and add that for you Link to comment Share on other sites More sharing options...
Guest MegaloManiac Posted December 25, 2006 Report Share Posted December 25, 2006 update GoHybrid: knowledge is free. post away. Regarding kinetik batteries: they are simply amped up starter batteries. it even says in their descriptions: more plates, tightly packed cells. That means there's plenty of lead-acid reaction and true to form they will make tons of current on demand, but i guarantee you, those things will let you down in a big way if you don't pay close attention to your charge/discharge habits. That means KEEPING the battery in a high state of charge, ESPECIALLY in cold weather. Remember starter batteries don't handle deep cycling well at all, and the more current you get from a battery that doesn't go up in size proportionally (to accomodate thicker plates) is only going to be more susceptible to the effects of sulfation... the fact some retailers refer to it as a deep cycle battery is misleading. Another thing to consider is the burden you're going to be placing on your alternator to keep that thing charged and maintained, particularly in addition to an existing battery. Frankly I don't see it happening. I think it's plenty telling that Kinetik offers chargers up to 120A (stupid high amount of current) to recharge their batteries with. Their smallest charger is 25A and even under the best circumstances, they're probably anticipating 4-6 hour charge times for a single battery. It doesn't sound from your description like you have 25 amps to spare at idle/cruise conditions for the duration you'd need it. I think your problem would be reduced significantly if not eliminated if you got a proper starting battery instead of your yellow top. Even Optima's website shows that for extended times (0-10 seconds) the Red tops can supply nearly 100 amps MORE current than the yellow top. Even an off-the shelf OEM starter battery will deliver more current than a Yellow top within just a few seconds. An extra 100 amps may be all you need. So why would you spend $500 on an ADDITIONAL kinetik battery that's going to be more tempermental and impose a bigger load on your alternator when in all reality you could probably spend that same amount and just get a second alternator? I say spend the smart money, ditch your yellow top and get a good starter battery. if you're stuck on brands too, then get an optima red top Link to comment Share on other sites More sharing options...
ChevyBoy Posted December 25, 2006 Report Share Posted December 25, 2006 thats some good info man Link to comment Share on other sites More sharing options...
Guest MegaloManiac Posted December 25, 2006 Report Share Posted December 25, 2006 Megalo: How about this, i purchase a red top place that under the hood and and throw the yellow in the trunk? But i am worried about what u said about charging and i have no way of isolating that battery without hookin it up to the hoodbattery to get charged through the alty GoHybrid: all i'm saying is that I don't think you need two batteries if you have the right one to begin with. If you are more than 100 amps deficient when your bass hits, I imagine you'd see worse problems than dimming lights. the topic of battery isolation has been covered before, but isolating one battery from the other doesn't eliminate the need to maintain a charge properly on both of them. Remember you're trying to free up as many spare amps as you can in between hits. batteries are, by nature, slow to recover and won't take best advantage of the kind of power your alternator CAN produce. If you can't isolate your batteries at all, then you're going to have a completely different issue where one battery has a higher state of charge than the other unless they're exactly the same battery. then the higher battery will try and charge the lower battery and i assure you it won't give a hoot about maximum charging current. So that means you can get lots of heat and overcurrent which are sure to diminish if not destroy your batteries. Link to comment Share on other sites More sharing options...
subaru18 Posted January 8, 2007 Report Share Posted January 8, 2007 So I have a red top under the hood, and a yellow top in the back, can someone explai to me why this is horrible and what to do to fix my system so that I don't have a sucky system because of this. Link to comment Share on other sites More sharing options...
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