can i run two batteries with my stock alternator?


Asked by Feb 12, 2013 at 05:46 PM about the 2004 Dodge Neon 4 Dr R/T Sedan

Question type: Car Customization

i have subs in my car lights are diming

28 Answers

Yes. No problem. It probably has a 60 amp alternator. Even if less, which I doubt, it will be fine You can upgrade to a 90 amp if you feel the need

6 people found this helpful.

The 2.0L has 85-100 amp alternators . The 2.4 turbo has 130-160 amp alternators listed on If you want to run dual batteries for your sound system you might want to isolate them. Use a regular battery for starting and a deep cycle or marine type for tunes.

8 people found this helpful.

Look for a capacitor for car audio systems. I would look into upgrading your alternator also.

1 people found this helpful.

You need to hook those batteries correctly or you will end up with 24 volt on a 12 volt system and that's not good for 12 volt wiring and you will be sorry. The following is how you will need to do it, If you are going to buy new 12 Volt or 6 Volt batteries for your car as your probably trying to power a monster stereo and this is how you'd want to do it for a RV also, it is important to know how to wire them properly so that you do not damage your cars electrical system. Although this is an easy concept to understand, many people tend to get this wrong. Basically, there are two ways to wire your batteries: in series or in parallel. In RVs where 6 Volt batteries are used, you may need to use a combination of both these methods to get 12 Volt output and increase the amount of total Amp Hours simultaneously. And as usual I don't do one liners so you might just want to cut and paste this and save it, so I'll provide some examples also, ok With batteries wired in series, the Voltage increases but the Amperage remains the same. Example: If you[ take two 6 Volt batteries] that have a capacity rating of 220 Amp Hours each and you wire them in series, you will get a total of [12 Volts] of power; however, the total Amp Hours will remain the same at a total of 220 Amp Hours. Now, here is what you need to pay special attention to, With batteries wired in series, [the positive (+) from one battery is connected to the negative (-) terminal of the other]. The remaining free positive (+) terminal and negative (-) terminal are used to connect to your RV. This is how you create 12 Volts from two 6 Volt batteries. Following is a graphic that represents two 6 Volt batteries wired in series.

34 people found this helpful.

OK, so that was two 6 volt batteries at 220 amp hours, now if you did the same with two 12 volt batteries you would have 24 volt in your car, and believe me, that's not good!! With batteries wired in parallel, the Voltage remains the same but the amperage increases. Example: If you take [ two 12 Volt batteries that have a capacity of 210 Amp Hours each] and you wire them in parallel, the Voltage will remain the same at 12 Volts; however, [ the total Amp Hours will increase to 420 Amp Hours]. And assuming and I'll bet your thinking stereo since it's a Dodge Neon, right??? OK, booming and you'll want it to last awhile while parked with your girl or well maybe other...LOL Need to be politically correct these days.With batteries wired in parallel, the positive terminal connects to the positive terminal of the next battery and the negative terminal connects to the negative terminal of the next battery. This is how you increase the total amount of Amp Hours you can get out of your battery bank, the following is a graphic that represents two 12 Volt batteries wired in parallel. So here's a pic of it,

41 people found this helpful.

This is about as big as you would want to go in your Saturn, any bigger which is possible and I have done it using just 6 volt batteries and placed like in the trunk, under rear seat, really not a good idea and just about every where I could find a space, wanted POWER. But with more power over the 12 volt parallel, like running 24 volt now you have to remember the wire from the batteries and size and what's there now is for 12 volt and if you try to run 24 volt, well just don't. So, what the heck, what if, suppose you do want to go crazy and have mass amp hours, Now if I want to ensure that I have more total Amp Hours for all my toys, all I have to do is take several of these 6 Volt battery combinations (that are wired in series to give me 12 Volts) and wire them in parallel. In this scenario we can take six – 6 Volt batteries and wired them in series and parallel to give us [12 Volts and 660 Amp Hours of battery capacity]. How did we end up with 660 Amp hours? Remember that each 6 Volt pair of batteries wired in series gives us 220 Amp hours. We have now wired the three pairs of batteries in parallel and when batteries are wired in parallel, the amperage increases. So since each pair produces 220 Amp Hours x 3 pairs = 660 Amp Hours total. Take a look at the diagram below and look closely as you don't want to screw up, but you probably won't be doing this but if someone else is reading this and has like an RV or 5th wheel, well this is what you want, for sure.

17 people found this helpful.

I know, WTF IlRegal, but look, one line answers can end up being regretful and I do things way right, always. And, OK sure I get maybe so technical or long in the answer it's annoying or overkill but I'd rather overkill than get someone killed. So, to me a simple, ya sure it'll work, ok really?? And I am not trying to offend anyone or everyone, but probably am, but dam let the person asking learn something and let them know what the consequences are for doing it wrong,, it pays off in the end run, and frankly maybe now you can see why sometimes one liner type answers can really be a problem for someone, like my biggest bitch is people here answering brake questions on this site. I suffered serious disabilities because someone didn't pay attention, and basically it was kind of like the person who screwed up asked someone a question and got a one or two line explanation. By giving a one or two line answer to a brake question, there are often other factors also and I know that the people that are asking the questions, even guys that are great mechanics at home or here on this site easily just take what would seem obvious to you, won't be obvious to the question person asking. So for example you have a guy at home who is a great shade tree mechanic but he is just not really absolutely positive about what ever, so he or she is doing and just looking for reassurance that what they might be thinking about doing or doing is right and heck talking to a Guru can be just all they needed to hear and all they needed to go get killed because they didn't get the complete picture. I am NOT trying to put down anyone's answers or anyone at all here, but sometimes the complete answer is necessary because what WE take for granted and just good ole common sense, is NOT what the person asking the question is hearing or reading, and look all of you fellas have seen these questions, and we laugh and say, geez just how stupid can you be, can you believe that question, yuk yuk, but you know what, they don't know, really. Why do windshield wipers go from right to left and not left to right?? Or, what is the spare tire for?? Sometimes it's so unbelievable to me that some people are even allowed to drive, it gets that worrisome for me anyhow. All right, you can now either just say it in public or go PM me and let me know just what a prick I am and or smart as@, that's all right, but I was going to say it anyhow, and if you don't know that by now, you do now. You all are the Guru's right??

8 people found this helpful.

Why not run a capacitor in the car instead of a second battery?

3 people found this helpful.

Yeah that is what I said, run a capacitor.

1 people found this helpful.

lol well money is kind of a problem anyways idk i heard capacitor dosent really work and i heard running a second batt. can kill my alt. idk,its only 85 amps and im running 5500 watt amp

2 people found this helpful.

I run a capacitor and I run two 3500 watt amps and 4 L7s.

1 people found this helpful.

Well, seems I spent a lot of time on an explanation that didn't really answer what you were thinking when asking about hooking up two batteries, but it was obvious what the need was for and a capacitor works great, if you get the right one, and that would have to be your decision, my explanation above I guess was regarding more on total amp hours that you would have and then with a proper capacitor for a system with a 5500 watt amp is workable for sure, but stop the engine how long will the system operate off a stock battery, is kind of what I was thinking and I guess I miss understood what you were trying to achieve. There's a lot of variables involved really, like RMS and woofers, how many etc. I dug around in my files and found a fairly good explanation about capacitors and what you will need to think about with your stereo and I thought this is the best way to explain it and get you in the right track and understanding, and the fact that capacitors just store and discharge power quick, so take a look and then maybe then the battery crap that I put up may make more sense, like hooking two twelves together and why, maybe LOL Keep a thought though that at 5500 watts you will want what is called a 5+ fraud capacitor which is good for about 2500 watts and up. But also it depends on a lot of things like I said a bit ago, but I hope this is better than my misunderstanding of your question, though I suspected it was for a stereo and not running a refrigerator in a RV, you'll probably get a bigger picture of what I meant after scanning this, again I hope, hard to tell, A car audio capacitor is an electrical circuit element used to store charge temporarily. This should not be confused with a battery, as a cap only temporarily holds a charge. It generally consists of two metallic plates separated by a dielectric. It is also used as a crossover component to filter out lower frequencies and allow higher frequencies to pass. Audio capacitors charge and discharge very fast, stabilizing the voltage to the amplifier. Stabilizing the voltage helps the amplifier stay cooler and run more efficiently because the amplifier is not straining to get the power it needs. Stabilizing the voltage helps an amplifier reduce distortion and produce more power consistently. A farad is the measurement unit used to determine the size of a capacitor. One farad to 500 watts RMS is the ratio used to determine the size of capacitor needed to supply enough power to an amplifier. While using a cap much larger than recommended will not damage an audio system, it is not recommended because of the unnecessary strain it puts on the vehicles electrical system. Installing a capacitor is a great way to help stabilize the voltage being sent to the amplifier. This where two 12v hook up is the deal.... This can help reduce the strain on the vehicle’s electrical system, reduce dimming lights, and improve sound quality of the audio system. Since each car is different and unique, knowing which capacitor is best for your system is important to know. If you made it this far, then I can tell you that a lot depends on the class of amp like class D or woofers, single coil, double etc. Lots of stuff. but just so I feel good about all the time I put explaining battery hooking, two twelves won't make you unhappy down the road,,, Good luck

5 people found this helpful.

capacitor is a waste. go the 2nd battery route. any audio shop out there thats any good at what they do will say youre doing this the right way.

7 people found this helpful.

Well, thanks Chase, I was feeling a bit like no one was getting it until you commented and you my friend are right, man, I spent a long time trying to explain this with the stupid pictures and all, but I appreciate someone who gets it and could come on board and say what I really didn't know about a stereo shop thoughts on this, I just know what I would do off the cuff if I was going to put a high powered stereo in my car and that's what I was trying to explain, but I didn't know that is exactly what a top notch stereo shop would do, so thanks for adding your comment on to my ridiculously long instruction manual....LOL

4 people found this helpful.

thanks man yeah its a class d 1ohm stable amp 5500 watts and well i have 4 12s but only running two of them they are pbx 4 ohm.. idk how many watts they are dont say on them..

Just watch how you marry the batteries together or you will learn how to re-wire your car, plus the pos. and neg. that goes from the the batteries may have to get bigger as they to are 12v rated.. Good luck, you have it

1 people found this helpful.

hey thanks for every one's help no i waNT to know what is the biggest battery i can replace with my stock battery is.. i want to most power i can get with out upgrading my altnater

Well, Steve, you don't have your monster cranking YET?? Dang bro, well I have showed you how to get most all your going to get really. And the alternator, voltage regulator and the battery are your three car electrical components, When you say biggest battery I know you don't mean size like two foot long by one foot wide and 120 lbs. I think your looking at what your doing all wrong here. I spent a lot of time to put together those diagrams for YOU, and really that's it on the battery idea, unless someone can tell me different which I am always into learning more about anything, and wouldn't feel insulted in the least. Without writing another huge how to for you, I would probably have to back up and explain Ohms Law, and then I would have to explain the entire electrical system and how the alternators and voltage regulators all work together, I am not being a wise ass to you as I have a lot invested into your success already. What you should ask is about cold cranking amps, and really for what your doing this isn't really any issue, wiring the two batteries like I showed you is enough... and changing the alternator isn't going to make any difference as far as I know in your power. A stock alternator is fine. You need to go back up 3 of my posts and re-read that and what I mentioned before. I have become a fan of the Optima batteries, but you also said you not real flush, and I took that as trying to do this on the cheap. Go start researching this on your own and go directly to auto stereo installation sites and see what they suggest and do. I am not a stereo installer and I have really told you about all I am capable of on this. You need to remember how much of your car depends on your electrical system working exactly right. Like your PCM, you pop a spark and your electrical system and things will get expensive and not what you want. So go to car stereo web sites and start reading, it can get deep but all you will want to know is out there and not really here. Please don't think I'm chasing you off, because your free here to ask what you want, but I don't really think your gonna get much more info than you have already gotten, at least here, just maybe somebody does have another solution and when they post it I'll know and I will come back and take a look at it, because if there is another work around on this I'd like to know myself. So, good luck Steven.. sincerely.

1 people found this helpful.

all I have to say is when I installed my capacitor I could tell a huge difference like night and day....I have 2 15" alpine type Rs with a 1600.1D Hifonics brutus elite,i replaced my stock battery with a shuriken SK-B120 its 2600 cranking amps and weighs 80 pounds...I also upgraded my wires tha "big 3" 0 guage but I couldn't figure out why my 1 HID kept turning off when I would crank it up so I put a 2.0 farad ABSOLUTE capacitor and to be honest it works better then my Rockford did and costed half the price...and that solved all my reads a constant 13.8 to 14.3

2 people found this helpful.

I think he's talking amps of a batt. I'll give you one word of advice. When hooking up second batt Make sure to get a charging dieod or that second or third batt will now be usedfor your starter and ththat's not good not to mention I melted a fuse and block cause I didn't have one. And all I was running was a 1000 amps batt and a 600 watts

1 people found this helpful.

not a answer,, QUESTION ?? Can I run two batterys cable pos to pos from bat #1 to bat # 2 and Neg to neg from bat #1 to bat # 2, And put a off and on switch in pos line on both bat. and switch one on and one off and it will only charge the one is on. Any one done this before. ????


jpchief all you have to do is get a $30 battery isolator that installs in minutes in line between your main and secondary batteries and you dont have to worry about anything. all you guys are making this way to hard!! a capacitor is only meant to supp;y a huge bust of energy (watts) at once. for instance you have your 4 12's cranked up full blast and it hits a super low hard note, the capacitor will supply the extra juice needed to make your speakers give what they're supposed to. now the secondary battery, which i personally think everyone running 500 rms or more should have, it takes the load off your cars electrical system by storing amps. if you are having a bunch of electrical problems, dim headlights and blown fuses the secondary battery will fix all of that. it will also save your cars alternator from prematurely going out. most of todays newer model cars that have electric everything on them already have a big enough alternators to support the secondary battery. like i said above, all you have to do is get the wire, secondary battery, and the battery isolator and your golden. WARNING!!!! do not just buy a $50 cheapo battery at walmart and throw anywhere in your car!!!! those batteries are "wet", meaning they have a mixture of approximately 60% water and 40% SULFURIC ACID!!! this will eat up anything it touches and if it gets to hot it will run out the top and make a hell of a mess. then on top of the eating part more important is the explosive fumes. most secondary batteries are put in trunks. and unlike under the hoods, most trunks are more air tight and hold those fumes in. after they build up all the need is a heat source or spark. yeppy, now you get it, all those subs amps and the rest of your stuff to make your speakers go boom can end up making your car go boom!! the batteries that are designed for this application are dry cell batteries and much, much safer!! they are more expensive too but come on you wasn't worried about a few dollars when you went from the 10's to the 12's or the 1500 watt amp to the 2500 watt amp now was ya? so stop whining and invest a little bit in something that is not only going to make your system run more efficiently and last longer but it will also take a lot of strain off your main electrical system and save you money on replacing that $250 or more alternator. i have a BMW with a stock 120 amp alternator so for me to spend $300 on a secondary battery seemed a lot at first but then i priced an alternator. $425!!! and that didn't include the voltage regulator or anything else that might have got fried in the process. most of you can get by with a $99 secondary battery. so your looking around $150-$175 by the time you buy your wire and isolator. i went bigger than what i need on both my capacitor and secondary battery. i have 2 Orion HCCA Series DVC Subwoofer 12" 5000W HCCA122 powered by a Orion - CO5000.1D - 5000W Monoblock Class D Cobalt Series Car Audio amp. then i have 2- 6.5" and 2- 5.25" with 2 satellite tweets, all Infinity Kappa powered by a Orion - CO5000.1D - 5000W Monoblock Class D Cobalt Series Car Audio amp. i've got a Orion - XTR-X4R - 4- Way Electronic Crossover Network w/ Remote Bass Booster and a Boss Audio 30 farad capacitor. my secondary battery is a XS Power D3100 and my head unit is a Orion AVR6.1 DAB+ Receiver. i've been lucky to have a brother in law that owns a car audio shop and i work for him so i don't have to pay retail but my equipment still was by no means cheap and i wanna protect it and the beemer its riding around in so i didn't cut corners and yes, went a little overboard with the capacitor and size of the secondary battery but, those 2 being oversized can't hurt anything. being undersized or nonexistent could be terminal for both my cars electrical system and the audio equipment both. so, the moral to my long ass post is to protect what you are investing your money in, your car and the audio equipment both and not only does it protect it but you will be amazed at the difference that comes out of your speakers as well!!

6 people found this helpful.

5500 watt amp....yea trust me upgrade alt and add second battery. I have a 2011 sentra runnin 4 12s on 2 6,000 watt amps at 1ohm. At first i had juss runnin on 1 6k at 2ohms and it still killed my battery and i have a 90 amp alt and yes i had a 6 farad capacitor. Caps are like sticking a bandaid on a wound that needs stitches. After 2 dead batteries i spent the money and upgraded to a 200 amp alt and 2 batteries, upgraded all power and ground cables to 0 guage and deleted the cap. I have those 2 6k amps pushin 4 12s and 1k amp pushin mids and highs and no dead batteries or dimming lights.


5500 watt amp....yea trust me upgrade alt and add second battery. You'll be glad.

1 people found this helpful.

Can I hook up 3 yellow top battery's to my stock car altonator

1 people found this helpful.

Honestly a lot of what I read here was right but there is some wrong too. Not calling you out at all Ilregal but an alternator upgrade does have a huge impact on a car audio system. Even if you get 4 batteries you will need something to charge them with to keep them at a proper charge. A car without any electronic upgrade meaning big 3, dry cell batts, alternator upgrades is only capable of putting out what it has to offer so say you have a 100 amp alt and while your car is running it uses say 40% of the power then then leaves you with 60 extra amps to work with, which if your running a little over 13volts that gives you 800 watts accessible. Now you can add in extra batteries but that's going to give you added power but it's a strain on your charging system and your alternator can't charge both of those extra batteries and your main battery all at maximum levels because it has a limit and wasn't built for that. Now if you upgrade to a bigger alt "keep in mind with a bigger alt you need a proper flow of power so this is where the big 3 comes in handy" but if you upgrade to a 240 amp alt then it's going to feed all of your batteries more power and in return feed your amp the power it wants. There is not a set up out there on stock electrical system running over 1200 true watts of power, and adding batteries can get you there but at the expense of your alternator. I have built many car audio set ups and in fact I still do it everyday but everything comes into play when you want a big power set up. You need proper wire size, proper charging units, your battery sizes, you will want to go with an isolator also and the right audio equipment that can handle it. I see people all the time claiming to have 4-5k systems and to run a system with true 5k watts you need at least one high output alts, multiple batteries, and do your homework on your wire set up because your going to have a whole lot of loot invested into just your power and ground wire because you will have true 0 gauge of wire and the high wattage game isn't cheap ha.

Ok I have read everything but I think still lost. Ok I have a 2005 Chevy silverado. I got 3 10" subs and only 250 amp for them...I know small at the moment. Planning on getting a bigger amp but just to be on the safe side, I have a 12v battery(battery #1) in the back of the truck and a 12v under the hood(battery #2) powering the truck. Don't have the money to get bigger wire yet but I have some extra 12 gauge copper wire around the house. Can I run that from battery 1 to 2, then the power wire which I think is 1 or 2 gauge wire from battery 1 to the amp which of course runs to my speakers and battery 2 hooked up like normal to truck under hood and it still be ok? The problem I'm having is that I got one battery running the system and truck and it's draining. With what I have is there any way to hook this all up and make stuff work right without fuckin shit up haha. Oh and also somewhere in all that hooking up I'm wanting to put in an (ON/OGG switch too) I can I do all this right without buying anything else. Is this possible is what I'm trying to ask and if so how?

Oh my truck is a 4.3 liter engine too

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