Is LifePo4 battery better than most linear power supplies?

[amit11]

I have been reading about lifepo4 battery. There were some threads mentioning it to use for allo digione signature. Also on net, there is some good information about it. Though it is not very much. The impression i m getting, it is better than most linear power supplies. Is anybody using it.. so wanted to know their experience. I already have allo Shanti linear power supply and am thinking to buy one more for my reclocker. So i am confused. Also the 18650 lifepo4 battery and its charger are not easily available.

 

[ajuvignesh]

I have been reading about lifepo4 battery. There were some threads mentioning it to use for allo digione signature. Also on net, there is some good information about it. Though it is not very much. The impression i m getting, it is better than most linear power supplies. Is anybody using it.. so wanted to know their experience. I already have allo Shanti linear power supply and am thinking to buy one more for my reclocker. So i am confused. Also the 18650 lifepo4 battery and its charger are not easily available.

Did you at last buy 18650 batteries?

 

[amit11]

Did you at last buy 18650 batteries?

Nope. I was not getting the confidence for it and availability was not easy as far as i remember. So i had gone ahead and bought another linear power supply. (Allo shanti)

 

[mbhangui]

Nope. I was not getting the confidence for it and availability was not easy as far as i remember. So i had gone ahead and bought another linear power supply. (Allo shanti)

1. The problem with batteries is that if you want a noise free operation, you have to use the battery without any regulator. In this case the voltage keeps on reducing as your music progresses.
2. If you want a constant voltage then you need to put few batteries in series to give higher voltage and then regulate it using a regulator which mostly is DC-DC convertors which are extremely noisy like SMPS. All power banks fall into this category. Solutions that use the 18650 batteries and provide 5v also use these noisy DC-DC convertors.
3. If you want a battery that gives you stable juice for very long hours, nothing at the moment beats the humble lead acid battery with a low noise constant voltage regulator. But using lead acid battery for music is hardly practical.

LPS is far superior to 1 and 2 and more practical than 3.

 

[ajuvignesh]

1. The problem with batteries is that if you want a noise free operation, you have to use the battery without any regulator. In this case the voltage keeps on reducing as your music progresses.
2. If you want a constant voltage then you need to put few batteries in series to give higher voltage and then regulate it using a regulator which mostly is DC-DC convertors which are extremely noisy like SMPS. All power banks fall into this category. Solutions that use the 18650 batteries and provide 5v also use these noisy DC-DC convertors.
3. If you want a battery that gives you stable juice for very long hours, nothing at the moment beats the humble lead acid battery with a low noise constant voltage regulator. But using lead acid battery for music is hardly practical.

LPS is far superior to 1 and 2 and more practical than 3.

So, I take LPS gives better sound quality than a mi 10k mah powerbank?

 

[mbhangui]

So, I take LPS gives better sound quality than a mi 10k mah powerbank?

Yes. A powerbank is no different than a SMPS

You won’t get a lower noise compared to a LPS, because the 5V are generated from a switching boost or buck converter (depending on the number of battery cells).
It is possible to get a good quality powerbank if they use a low noise regulator like the one used in LPS. But that would increae the cost of the power bank and I have not come across a power bank targetted at audiophiles.

 

[ajuvignesh]

Yes. A powerbank is no different than a SMPS

You won’t get a lower noise, because the 5V are generated from a switching boost or buck converter (depending on the number of battery cells).

Thank you so much. I was in an impression that batteries are superior to LPS. Time to get an allo shanthi.

 

[mbhangui]

Thank you so much. I was in an impression that batteries are superior to LPS. Time to get an allo shanthi.

Batteries are superior if used without any regulator or electronics. But there is no battery in this world that gives you exact 5v. So you have to use electronic switching to use either boost converter to increase the voltage or buck converter to decrease the voltage. Both of these are switching regulators and hence induce noise in the circuit.

The other option is to use batteries with low noise regulators like the old LM317. But the regulation comes at a cost. Excess power is thrown away as heat and your battery will run down faster compared to a normal power bank.

 

[ajuvignesh]

Batteries are superior if used without any regulator or electronics. But there is no battery in this world that gives you exact 5v. So you have to use electronic switching to use either boost converter to increase the voltage or buck converter to decrease the voltage. Both of these are switching regulators and hence induce noise in the circuit.

The other option is to use batteries with low noise regulators like the old LM317. But the regulation comes at a cost. Excess power is thrown away as heat and your battery will run down faster compared to a normal power bank.

Got it. Thanks again sir The Shanti is currently out of stock. Will purchase it once it is available again.
So, from my understanding, basically the wall warts and powerbanks negotiate with the device and give out the required power. For example, My WiiM is 1A 5V I guess, The apple wall wart and the powerbank supply 1 A 5V to the WiiM. Does shanti too negotiate with the device and send only required power or will it send the full 5.2V 3A or 5.2V at 1.2A to the device?

 

[mbhangui]

Got it. Thanks again sir The Shanti is currently out of stock. Will purchase it once it is available again.
So, from my understanding, basically the wall warts and powerbanks negotiate with the device and give out the required power. For example, My WiiM is 1A 5V I guess, The apple wall wart and the powerbank supply 1 A 5V to the WiiM. Does shanti too negotiate with the device and send only required power or will it send the full 5.2V 3A or 5.2V at 1.2A to the device?

There is absolutely no negotiation happening.

Your WiiM needs 5v and the max current it will draw is 1A. It doesn't mean that the WiiM will always be consuming 1A. All you need to understand is that the regulator tries to maintain a constant voltage. When your WiiM draws more current, the voltage will fall down. this will be sensed by the regulator chip and it will increase the voltage till it reaches 5v. When the WiiM starts drawing less current, the voltage will increase. This again will be sensed by the regulator which will decrease the current and hence bring the voltage down. This happens at very high speed and hence if you have a voltmeter connected you will never see a dip or a rise as you are playing music. Also all of these supplies have capactitors at the output which further help in keeping the voltage steady.

This is analogous to you driving a car. When you start climbing, you need more power. Hence you will press the accelerator to keep the speed constant. And when you go down the hill you will remove your foot from the accelerator. Another method to keep constant speed is to change gears. When you are going up hill and speed starts reducing, change the gear to a lower slot.

Switching regulators are like when you use accelerator to always control the speed. You car is always at the highest gear and you keep on pressing and releasing the accelerator every few seconds. If you want to go fast, you will keep the accelerator pressed for longer time and then release it. Since you are using a high gear you use less petrol. In this case we also do not use brakes to slow down.

Non switching regulators are like using gear with your accelerator at a fixed postion. When you want to go slow, you put the car in First gear and waste petrol or you use brakes. When you suddenly want speed you just change the gear to a higher slot or you release the brakes. Since you use a lower gear or using brakes, you are always using more petrol. Not sure If I could explain the concept of regulation. But regulation is either by using high speed switching or by wasting excess power in the form of heat. The buck/boost convertors use the switching method. LPS uses the second method of wasting excess power as heat.

Another analogy is that the buck/boost and SMPS regulators are like your Class D amplifiers and the LPS is like your Class A amplifier.

 

[bornfi]

An LPS is always better because based on some experiments I did in the past and my reading on the internet suggest that, in simple terms, batteries are not able to provide the power at the speed the music system needs it so ultimately, your music might sound dull. But this is my experience and with whatever limited knowledge I have, what I know is that batteries do not have the discharge speed of a capacitor (used in LPS).

 

[mbhangui]

what I know is that batteries do not have the discharge speed of a capacitor (used in LPS).

And that's a reason all power supplies use capacitor banks. A capacitor also helps in maintaing stable voltage. It is analogous to a heavy platter on a turntable. Because of the high mass of the platter the speed cannot suddenly increase or decrease,

Similarly with a large capacitor bank it is difficult to suddenly increase the voltage. When the demand goes high, the voltage cannot decrease becaue the capacitor then starts supplying power from it's reserve charge.

 

[ajuvignesh]

There is absolutely no negotiation happening.

Your WiiM needs 5v and the max current it will draw is 1A. It doesn't mean that the WiiM will always be consuming 1A. All you need to understand is that the regulator tries to maintain a constant voltage. When your WiiM draws more current, the voltage will fall down. this will be sensed by the regulator chip and it will increase the voltage till it reaches 5v. When the WiiM starts drawing less current, the voltage will increase. This again will be sensed by the regulator which will decrease the current and hence bring the voltage down. This happens at very high speed and hence if you have a voltmeter connected you will never see a dip or a rise as you are playing music. Also all of these supplies have capactitors at the output which further help in keeping the voltage steady.

This is analogous to you driving a car. When you start climbing, you need more power. Hence you will press the accelerator to keep the speed constant. And when you go down the hill you will remove your foot from the accelerator. Another method to keep constant speed is to change gears. When you are going up hill and speed starts reducing, change the gear to a lower slot.

Switching regulators are like when you use accelerator to always control the speed. You car is always at the highest gear and you keep on pressing and releasing the accelerator every few seconds. If you want to go fast, you will keep the accelerator pressed for longer time and then release it. Since you are using a high gear you use less petrol. In this case we also do not use brakes to slow down.

Non switching regulators are like using gear with your accelerator at a fixed postion. When you want to go slow, you put the car in First gear and waste petrol or you use brakes. When you suddenly want speed you just change the gear to a higher slot or you release the brakes. Since you use a lower gear or using brakes, you are always using more petrol. Not sure If I could explain the concept of regulation. But regulation is either by using high speed switching or by wasting excess power in the form of heat. The buck/boost convertors use the switching method. LPS uses the second method of wasting excess power as heat.

Another analogy is that the buck/boost and SMPS regulators are like your Class D amplifiers and the LPS is like your Class A amplifier.

Thank you for the detailed explanation with analogies. So, even if I connect the 5.2V 3A of shanti to the wiim mini which needs 5V 1A, wiim mini only consumes the max 5V 1A and shanti wastes the excess power as heat and no damage is done to wiim mini. Correct?

 

[mbhangui]

Thank you for the detailed explanation with analogies. So, even if I connect the 5.2V 3A of shanti to the wiim mini which needs 5V 1A, wiim mini only consumes the max 5V 1A and shanti wastes the excess power as heat and no damage is done to wiim mini. Correct?

Correct. The wastage is happening inside shanti.

 

[ajuvignesh]

Correct. The wastage is happening inside shanti.

Got it sir.

 

[ajuvignesh]

An LPS is always better because based on some experiments I did in the past and my reading on the internet suggest that, in simple terms, batteries are not able to provide the power at the speed the music system needs it so ultimately, your music might sound dull. But this is my experience and with whatever limited knowledge I have, what I know is that batteries do not have the discharge speed of a capacitor (used in LPS).

With battery setup wiim sounds good. Can't wait to try it with LPS.

 

[keith_correa]

So, even if I connect the 5.2V 3A of shanti to the wiim mini which needs 5V 1A, wiim mini only consumes the max 5V 1A and shanti wastes the excess power as heat and no damage is done to wiim mini. Correct?

No! You typically should not supply excessive voltage to a device rated for a lesser operating voltage. In your case of 5.2V vs. 5V, the difference is marginal so it will not affect/damage the device but otherwise where the difference is large...
In your case 5.2V WILL be supplied by the LPS, FWIW.
As for amperage, the device will draw whatever it needs subject to the PS being able to supply.

 

[sidvee]

Thank you for the detailed explanation with analogies. So, even if I connect the 5.2V 3A of shanti to the wiim mini which needs 5V 1A, wiim mini only consumes the max 5V 1A and shanti wastes the excess power as heat and no damage is done to wiim mini. Correct?

What kind of cable are you planning on using to connect the LPS to the mini? Does the shanti come with a usb out?
Cheers,
Sid

 

[ajuvignesh]

What kind of cable are you planning on using to connect the LPS to the mini? Does the shanti come with a usb out?
Cheers,
Sid

I guess shanti is shipped with various adaptors.

 

[Kannan]

What kind of cable are you planning on using to connect the LPS to the mini? Does the shanti come with a usb out?
Cheers,
Sid

it comes with type C extension cable. So can be directly connected to type C input devices.
I have also used it with Chromecast Audio using a type C to miniUSB adapter