Menu
Forum
What's new
New posts
Live Activity
Search forums
Members
Registered members
Classifieds Member Feedback
Car Audio Discussion
General Car Audio
Car Audio Build Logs
Car Audio Equipment
Subwoofers
Speakers
Amplifiers
Head Units
Car Audio Help
Wiring, Electrical and Installation
Enclosure Design & Construction
Car Audio Classifieds
Car Audio Classifieds
Car Audio Wanted
Classifieds Member Feedback
Gallery
New media
New comments
Search media
SHOP
Shop Head Units
Shop Amplifiers
Shop Speakers
Shop Subwoofers
Shop eBay Car Audio
Test
Forum
Search
Search titles only
Search titles only
Log in / Join
Search
Search titles only
Search titles only
What's new
New posts
Live Activity
Search forums
Members
Registered members
Classifieds Member Feedback
Menu
Reply to thread
Forum
Car Audio Help
Wiring, Electrical & Installation
Good battery for a 5k install w 320 amp alternator?
JavaScript is disabled. For a better experience, please enable JavaScript in your browser before proceeding.
You are using an out of date browser. It may not display this or other websites correctly.
You should upgrade or use an
alternative browser
.
Message
<blockquote data-quote="hispls" data-source="post: 8736806" data-attributes="member: 614752"><p>Fortunately if you're trying to DIY there's a couple machine shops that are building ready-made bus bars for the popular lithium cells so if you can figure out how to line up the - and + in a flashlight you can probably sort out busing cells. The only thing you'll need to be a little handy to sort out is a secure mounting location for them somewhere inside the cabin (they may not like the heat under the hood). My brother and I bought some copper bar stock from a place out west and nuts and washers from Fastenall and did that all ourselves but it was definitely a PITA so unless you just like a challenge or have some decent metalworking tools you should stick to some ready-made solution there I think.</p><p></p><p>At least one of these "'professional" battery brands is claiming you can use their LTO banks with your AGM which is probably true. It'll certainly help. But I believe they're just relying on the huge life expectancy of that technology so that even if the buyers are doing shitty installs they'll still outlast their warranty. Conventional wisdom used to be to not even mix and match different types/brands of lead acid batteries, and it's a testament to marketing that these companies have convinced much of the market that mix matching different chemistry batteries is now fine. I'd say mix matching lead acids probably only becomes really detrimental as things age though. First couple years I don't expect it would make much difference if any. In short, mix matching is definitely not doing it correctly and you will be sacrificing performance and life expectancy of your batteries. </p><p></p><p>Your alternator will put out that "rating" ONLY at some certain RPM (2000 or a bit more usually) and only before it gets hot (which won't take long in real world applications). Provided you've bought from a known reliable brand you've done as much as you can on that front so don't sweat it, but do be aware that you can't plan on (I definitely already have 350A of what this amp wants to eat). The other piece of that puzzle is that alternator cannot deliver instant burst power. Your battery needs to do that and keep things buffered until the alternator can load down and deliver more.</p><p></p><p>That Sundown amp will make over 5000W into 2 ohm so you may well be seeing that, and real world real time efficiency may not be as great as whatever bench test or published stat you might be using to plan around. I'm running 240AH of YingLong LTO cells and voltage won't drop more than 0.2V with a single SFB8000 running a pair it will dip about 0.8V if you're riding it hard. Certainly I could probably get away with less but we bought these before anybody in the USA was using them so I figured if I over built enough that even if they only performed half as well as specs claim that I'd only ever really need half of that. Fortunately as it turns out these things actually do deliver as advertised, but now I'm in a great position where I'm never really demanding too much from them. If you look at performance and life cycle data on batteries you lose both performance and service life much more quickly the closer you approach maximum safe ratings.</p><p></p><p>That all said, you may get by with less battery so you could possibly just buy one 6S bank and see what happens and add more until you're satisfied. We cannot predict how you're going to play music nor impedance curve of your box installed so nobody can tell you what your real current demands will be. I will suggest that you may well have enough power on tap to smoke your 3 woofers though if you're not careful so do go easy at first until you get a feel for how they're holding up once you get going. You will have little to no warning signs (smell) if you're getting into thermal limits if you're running sealed box and you definitely don't want to melt voice coils your first week out the gate.</p></blockquote><p></p>
[QUOTE="hispls, post: 8736806, member: 614752"] Fortunately if you're trying to DIY there's a couple machine shops that are building ready-made bus bars for the popular lithium cells so if you can figure out how to line up the - and + in a flashlight you can probably sort out busing cells. The only thing you'll need to be a little handy to sort out is a secure mounting location for them somewhere inside the cabin (they may not like the heat under the hood). My brother and I bought some copper bar stock from a place out west and nuts and washers from Fastenall and did that all ourselves but it was definitely a PITA so unless you just like a challenge or have some decent metalworking tools you should stick to some ready-made solution there I think. At least one of these "'professional" battery brands is claiming you can use their LTO banks with your AGM which is probably true. It'll certainly help. But I believe they're just relying on the huge life expectancy of that technology so that even if the buyers are doing shitty installs they'll still outlast their warranty. Conventional wisdom used to be to not even mix and match different types/brands of lead acid batteries, and it's a testament to marketing that these companies have convinced much of the market that mix matching different chemistry batteries is now fine. I'd say mix matching lead acids probably only becomes really detrimental as things age though. First couple years I don't expect it would make much difference if any. In short, mix matching is definitely not doing it correctly and you will be sacrificing performance and life expectancy of your batteries. Your alternator will put out that "rating" ONLY at some certain RPM (2000 or a bit more usually) and only before it gets hot (which won't take long in real world applications). Provided you've bought from a known reliable brand you've done as much as you can on that front so don't sweat it, but do be aware that you can't plan on (I definitely already have 350A of what this amp wants to eat). The other piece of that puzzle is that alternator cannot deliver instant burst power. Your battery needs to do that and keep things buffered until the alternator can load down and deliver more. That Sundown amp will make over 5000W into 2 ohm so you may well be seeing that, and real world real time efficiency may not be as great as whatever bench test or published stat you might be using to plan around. I'm running 240AH of YingLong LTO cells and voltage won't drop more than 0.2V with a single SFB8000 running a pair it will dip about 0.8V if you're riding it hard. Certainly I could probably get away with less but we bought these before anybody in the USA was using them so I figured if I over built enough that even if they only performed half as well as specs claim that I'd only ever really need half of that. Fortunately as it turns out these things actually do deliver as advertised, but now I'm in a great position where I'm never really demanding too much from them. If you look at performance and life cycle data on batteries you lose both performance and service life much more quickly the closer you approach maximum safe ratings. That all said, you may get by with less battery so you could possibly just buy one 6S bank and see what happens and add more until you're satisfied. We cannot predict how you're going to play music nor impedance curve of your box installed so nobody can tell you what your real current demands will be. I will suggest that you may well have enough power on tap to smoke your 3 woofers though if you're not careful so do go easy at first until you get a feel for how they're holding up once you get going. You will have little to no warning signs (smell) if you're getting into thermal limits if you're running sealed box and you definitely don't want to melt voice coils your first week out the gate. [/QUOTE]
Insert quotes…
Verification
Post reply
Forum
Car Audio Help
Wiring, Electrical & Installation
Good battery for a 5k install w 320 amp alternator?
Top
Menu
Home
Refresh