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The Maxwell version is limited to 25A charging... which supports my theory from a week ago that the balancing cannot be overly fast.

I think you may want to investigate it all pretty thoroughly.
what Maxwell version and where did you find the inrush specs? Did someone delete a post or I missed something lol How can a supercap bank have a low inrush of 25A?

what is this ioxus cap bank your looking at and why? It’s a 12v bank. You would want a 16v if using a high output alternator that charges at 15v.
also if I’m reading it’s specs correctly it’s charging is 15a/21A max That’s lower than the maxwell mentioned.

I doubt anyone will find the inrush specs for any xs power cap banks.
Maybe we are misunderstanding this inrush specs.
I’ve seen maxwell superbanks , xs power and the cheaper eBay banks

So it must be possible the inrush specs are good enough.

FishChris you know the xs power banks that look like a battery are just caps like what you allready have with the cheap balance boards instead of bars. Is it possible you are overthinking this supercap thing too much? 😜 People hook up hundreds of the cells with zero balancing boards and your worried about 6 not being balanced? Didn’t you also buy the eBay cap bank? That one has balance boards. Hook that one up or sell me whichever you don’t want 😉 I could care less if they balanced. Is it possible the balancing is what makes them charge slower?
 

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@Selkec the maxwell 31/1800 and the 31 is the battery class, and the 1800 refers to the CCA.
It basically charges to then deliver enough of
 

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what Maxwell version and where did you find the inrush specs? Did someone delete a post or I missed something lol How can a supercap bank have a low inrush of 25A?

what is this ioxus cap bank your looking at and why? It’s a 12v bank. You would want a 16v if using a high output alternator that charges at 15v.
also if I’m reading it’s specs correctly it’s charging is 15a/21A max That’s lower than the maxwell mentioned.

I doubt anyone will find the inrush specs for any xs power cap banks.
Maybe we are misunderstanding this inrush specs.
I’ve seen maxwell superbanks , xs power and the cheaper eBay banks

So it must be possible the inrush specs are good enough.

FishChris you know the xs power banks that look like a battery are just caps like what you allready have with the cheap balance boards instead of bars. Is it possible you are overthinking this supercap thing too much? 😜 People hook up hundreds of the cells with zero balancing boards and your worried about 6 not being balanced? Didn’t you also buy the eBay cap bank? That one has balance boards. Hook that one up or sell me whichever you don’t want 😉 I could care less if they balanced. Is it possible the balancing is what makes them charge slower?
Let’s try and educate a little bit here, you have lots of ‘facts’ crossed up here...

the balance boards don’t fit instead of the bars 🙈 they fit across two cells a piece... in parallel to the bars

the guys who run multiple cells without balancing are likely to be balancing the caps by nature of some in parallel being higher and lower than the others, therefore they effectively balance themselves by nature of being in parallel with one another, so you need balance boards way less than with six individual caps... please work out why people do what they do while applying it to other people’s setups...

balancing caps doesn’t make them charge slower, they are exactly the same speed charging as no balance boards below 2.6v

balance boards from eBay and on the packs are more like limiting boards, I know the ones I have just acquired are only bleeding off current when the voltage gets to 2.7v, they aren’t as advanced as some... for example sab ic’s are way more effective than a single semiconductor like the d1804 on my boards... they progressively bleed off current per cap in a progressive manner as voltage gets towards a set point

I don’t know where Holmz got 25a current from, if depleted a cap can pretty much take instantaneously a hell of a lot of current... the only time it needs to be limited is if way over voltage ie 2.7v for a 2.7v cap bank as that’s when the balance board is doing its job, if it’s at 14.4 (2.4v per cap) the current can be whatever you like, it will charge and discharge as fast and with as much current you can give it, and with a voltage regulated source like an alt it will never get anywhere near it’s limits as when the voltage gets to 2.4v per cap the current naturally tails off much like a battery...

so if charging at the limits of the caps when the boards do something you would just make sure you never set the voltage to 16.2v, otherwise you’d be fine... and let’s face it id be more worried about batterys boiling at that voltage... so unless your pushing limits 25a isn’t even a thing
 

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@dumdum that maxwell unit said something like 15 or 25A, so it must have some current limiter on the charge side. (maxwell 31/1800)

I assume that the 58F banks are different beast to a battery sized replacement... so it is sort of a set of questions from me,
 

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@dumdum that maxwell unit said something like 15 or 25A, so it must have some current limiter on the charge side. (maxwell 31/1800)

I assume that the 58F banks are different beast to a battery sized replacement... so it is sort of a set of questions from me,
that battery made of caps will likely be a 500f block made of six 3000f caps, the size is about right for that...

Now you’ve mentioned what you mean, I would presume the (from the battery) in brackets is a bit of a limitation... that unit is likely just 6 caps in parallel, if you connect it while discharged to a power supply it sure will slurp some current, way more than 25a, that’s why you would always charge it through a light bulb ideally to stop you welding the leads to the voltage source

Note other conditions listed in brackets and very careful wording... it doesn’t say it will forever be limited if just used in parallel like Chris is intending, and yes I’d think it would have balance boards built in 👍🏼

spec sheets are one thing... but you should read into them a little more before drawing conclusions, that spec sheet for the Maxwell cap bank is produced as a vehicle starting battery, it will discharge way faster than 25a... it’s designed for starting trucks, generally if it can discharge that fast it will recharge just as quick

Even the one that Chris posted at the start gets a mention of how fast it charged again once it had held the voltage up to 13.25v, it flew back up to 13.6 almost instantaneously as soon as the load was removed
 

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that battery made of caps will likely be a 500f block made of six 3000f caps, the size is about right for that...

Now you’ve mentioned what you mean, I would presume the (from the battery) in brackets is a bit of a limitation... that unit is likely just 6 caps in parallel, if you connect it while discharged to a power supply it sure will slurp some current, way more than 25a, that’s why you would always charge it through a light bulb ideally to stop you welding the leads to the voltage source

Note other conditions listed in brackets and very careful wording... it doesn’t say it will forever be limited if just used in parallel like Chris is intending, and yes I’d think it would have balance boards built in 👍🏼

spec sheets are one thing... but you should read into them a little more before drawing conclusions, that spec sheet for the Maxwell cap bank is produced as a vehicle starting battery, it will discharge way faster than 25a... it’s designed for starting trucks, generally if it can discharge that fast it will recharge just as quick

Even the one that Chris posted at the start gets a mention of how fast it charged again once it had held the voltage up to 13.25v, it flew back up to 13.6 almost instantaneously as soon as the load was removed
I have to agree! Any supercap bank is going to take much much more than 25A. Not sure why maxwell says that. The loxus also states about the same! But I gaurantee if you hook one of them uncharged up to yoir system it’s going to suck every bit of power that it can and weld stuff together and possibly blow something. It they were limited to 25A they would it do this. And it’s most likely that the loxus, maxwell and xs capacitors that look like batteries all have the same type of cells in parallel to them.
 

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I have to agree! Any supercap bank is going to take much much more than 25A. Not sure why maxwell says that. The loxus also states about the same! But I gaurantee if you hook one of them uncharged up to yoir system it’s going to suck every bit of power that it can and weld stuff together and possibly blow something. It they were limited to 25A they would it do this. And it’s most likely that the loxus, maxwell and xs capacitors that look like batteries all have the same type of cells in parallel to them.
^Whatever...^
You are totally discounting the idea pf a diode in there and a limited flow inwards.

And the "I guarantee" part seems meaningless if neither one of us understand what this beast is. The only sure gaurantee right now is that we both don't know.

This Maxwell is totally NOT what Chris would be wanting.
 
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Discussion Starter #32
Well, both the Xs Power and the Ioxos are designed... Or at least expected to be used on high powered car audio systems. SMD us d the Xs brand (4 of them) on his system and seemed pretty happy with them, and EXO is using the one in the video I posted in a high powered system and he loves it too.

So, since I made enough $ last week to buy 6 of these things, I think I'm going to just go on and buy one, and try to get rid of my 6 Limitless caps later...
 

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Well this interests me, but the Maxwell being input current limit points out to me that I do not under what they are doing, other than intentionally protecting the alternator from having to do more that it can.
But it also makes me wonder how the balances work, and whether it is similar to the Maxwell, or whyether they can inrush a lot more current!

Hopefully @Selkec or @dumdum understand the nuance and can explain it to me (us)... please.
 

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Well this interests me, but the Maxwell being input current limit points out to me that I do not under what they are doing, other than intentionally protecting the alternator from having to do more that it can.
But it also makes me wonder how the balances work, and whether it is similar to the Maxwell, or whyether they can inrush a lot more current!

Hopefully @Selkec or @dumdum understand the nuance and can explain it to me (us)... please.
See below 👍🏼
 

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Reading a bit more the engine start module is literally just to supply the starter motor... it has an in and an out for current with a common Earth... it’s not what we are after at all... the batterys charge the caps and then the starter alone fires off the caps, it can take 30 mins to charge the caps, hence the limit... I’m guessing it can also charge like some of the booster packs using 50% depleted batterys and still build a big enough charge to start a vehicle (I was amazed when I first saw a little box start a flat van)

in short it will have a little step up to up the voltage from semi flat batterys to get the caps upto a good voltage and then use all the saved power to start the truck... I can think of stuff like ice road truckers where you wouldn’t want to get stranded where it could be very handy 👍🏼

Edit... reading a bit more it will take a voltage of 12.6-12.8v and charge the caps to 14.5-16.2v ie a higher voltage and more energy to give any starter motor a good power boost to help starting motors, you literally run the starter main power cable from it, the rest of the vehicles setup runs from the 12v batterys also fitted to the vehicle 👍🏼

there ya go... it’s not a pure cap bank like the Xs power and super cap banks like mine are... you wouldn’t use it for what we are requiring it for as it’s designed for something very different
 

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^Noice!^
So those balance boards from earlier, are nothing like a step up transformer in the Maxwell...
And they can suck down tonnes of charge and be in balance?

I am considering a Maxwell for a starter battery, as I need a new one. If it lasts longer than a chameical battery.
 

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^Noice!^
So those balance boards from earlier, are nothing like a step up transformer in the Maxwell...
And they can suck down tonnes of charge and be in balance?

I am considering a Maxwell for a starter battery, as I need a new one. If it lasts longer than a chameical battery.
You need to read what you write as I’m sure some of it means something to you... but I often get lost trying to follow what you mean... 🙈

the Maxwell you listed is only for the starter, it won’t run a car, you need to run the car off another battery

As for balance boards... which ones are you talking about as two different sorts have been listed... you bounce round like zebidee...

I wouldn’t say any balance board can suck down ‘tons of current’... they aren’t designed to take much Current at all, they count on you having a clue... there’s a limit to how much heat two resistors can dissipate... and that’s literally what occurs... once the board sees 2.69v it allows current to pass through the transistor via the resistors to Earth... this allows the cap voltages on lower caps to rise and equalise...

it won’t do anything at 2.5v per cap for example from what I can see in my simple boards... the other boards I found are available in different voltage specs and are more progressive at bleeding current off
 

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Discussion Starter #38
Well, I know I've been bouncing around, and I did look at that Ioxis brand 375 Farad bank....
But ended up going with this one...

2-4 weeks delivery time... But what the hey, I've been waiting months now anyway. Maybe by then, I'll have a little more free time to actually drive the truck and listen to the stereo....
 
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