LifePO4 MKII does not charge anymore.
Yesterday I have altered the setup of my LifePO4 MKII board. At first I had it running with 10 batteries and it charged properly. Now I've changed the setup to 4 batteries only with the TP7-TP8; TP9-TP10; TP7-TP8; TP11-TP12 and the TP1-TP2; TP3-TP4; TP5-TP6 shorted so that the rails all output 3.3V.
But now it does not charge anymore. It immediately goes in pending state after showing a voltage of 3.40V. But none of the 4 batteries has a charge of 3.40V. They all are approximately 3.3V. I checked the 0.15 Ohms resistors on the back side and they all same to be ok. I also reflowed some of them but to no avail. It alway goes immediately in pending state. When I change the end charge voltage to 3.41V. It starts charging but then goes to pending state after a few seconds and than it starts charging again for a few seconds thus some kind of loop...
Has anyone experienced this behavior before? And is there anything else that has to be checked besides the 0.15 Ohm resistors?
Yesterday I have altered the setup of my LifePO4 MKII board. At first I had it running with 10 batteries and it charged properly. Now I've changed the setup to 4 batteries only with the TP7-TP8; TP9-TP10; TP7-TP8; TP11-TP12 and the TP1-TP2; TP3-TP4; TP5-TP6 shorted so that the rails all output 3.3V.
But now it does not charge anymore. It immediately goes in pending state after showing a voltage of 3.40V. But none of the 4 batteries has a charge of 3.40V. They all are approximately 3.3V. I checked the 0.15 Ohms resistors on the back side and they all same to be ok. I also reflowed some of them but to no avail. It alway goes immediately in pending state. When I change the end charge voltage to 3.41V. It starts charging but then goes to pending state after a few seconds and than it starts charging again for a few seconds thus some kind of loop...
Has anyone experienced this behavior before? And is there anything else that has to be checked besides the 0.15 Ohm resistors?
I upgraded my system today, the power supply section is now:
1. LifePO4 MKII
2. UcAdapter PCB
3. UcMateConcitioner (5V)
4. UcHybrid (3.3V 4x)
The upgrading job was pretty easy and straight froward. Both MKII and MKIII are good to go. MKIII will have some dedicated connectors. The integration was seamless. When I turned it on, everything was OK. The blue conditioning LED started lit in a couple of second. No smoke, no fire.
I have some new discovery and still feel the improvements.
The small board behind my PRi DAC stack is my HDMI receiver board. I use it to receive the true DSD signal the I hacked from my Oppo bluray/SACD player through ReceiverPi.
UcUpgradeKitIntegration by Ian, on Flickr
UcUpgradeKitIntegration1 by Ian, on Flickr
Ian
Amazing work - but what are the resultant improvements in sound?
Just found this - looks like someones already powered 2 x NUCs using Ians LifePO4 boards. Reviewer says it better than Paul Hynes SR4. Great praise indeed
A novel way to massively improve the SQ of computer audio streaming - Page 560 - Music Servers - Audiophile Style
A novel way to massively improve the SQ of computer audio streaming - Page 560 - Music Servers - Audiophile Style
I'm having the same exact issue with mine. The 0.015R resistors all look normal, but they all measure at least 0.2 ohms. From previous posts and from what's in the manual, it looks like they need to be changed (although on mine, all of the 0.015R seem bad despite only using 4 batteries).
Did you measure the resistors with a DMM?
Well all my 0.015R resistors also measure 0.2 ohms with a DMM. But I once did acquire a new batch of those resistors and they also measure 0.2 ohms so I don't think this is the problem. Also on another LilfePO4 board I'm having they all measure 0.2 ohms. Maybe @Ian can shine some light on the matter?
Hello,
If you need them to be 0,015 i would just order the well known brands at a well known supplier and ask for 1% tolerance, If this is a critical value in the circuit the kit should contain these kind of parts at some extra cost.
You could also set up a temporary CRC suoply loaded with a resistor that will ask a serious current and put the 0,015 ( or a string of them) in series with the R in the CRC and calculate the R by using the voltage drop. greetings, eduard
If you need them to be 0,015 i would just order the well known brands at a well known supplier and ask for 1% tolerance, If this is a critical value in the circuit the kit should contain these kind of parts at some extra cost.
You could also set up a temporary CRC suoply loaded with a resistor that will ask a serious current and put the 0,015 ( or a string of them) in series with the R in the CRC and calculate the R by using the voltage drop. greetings, eduard
Do you mean the supplied resistors on the LifePO4 board are just crap? And that they always should be replaced? Why would I buy a board for $189,99 to have crap resistors on them? And I'm still not sure if the resistors are the problems. So even when I replace them would the board function as it should in the first place? The board did function with 10 batteries but now with only 4 batteries it does not function anymore? Why?
Hello,
If the value of the resistors isnt right and because of this the circuit is not working then these resistors should be replaced. BUT i think i Ian would not include low quality resistors if that would give boards that probably could het the owners into trouble!
Better wait for him to respond. It could just be a bad solder joint.
Greetings, Eduard
If the value of the resistors isnt right and because of this the circuit is not working then these resistors should be replaced. BUT i think i Ian would not include low quality resistors if that would give boards that probably could het the owners into trouble!
Better wait for him to respond. It could just be a bad solder joint.
Greetings, Eduard
Our issue with measuring the resistors comes down to the DMM and test leads: given the very low resistance we are effectively measuring our test lead's resistance. I tried a higher precision DMM and much shorter test leads and the resistors measured fine (also a 4-wire measurement on a removed resistor confirmed it).
I got a reply from Ian: the 3.35V end charging voltage was for calibrated for 10 battery cells. In order to charge only 4 batteries, we must increase the end charging voltage to 3.48V.
Paul
I got a reply from Ian: the 3.35V end charging voltage was for calibrated for 10 battery cells. In order to charge only 4 batteries, we must increase the end charging voltage to 3.48V.
Paul
Hi Paul,
I tried what Ian suggested to you and I increased the end charging voltage to 3.48V but after it goes to pending state it starts to charge again after a few seconds. In the pending state it shows a voltage of 3.37V. Is this also something that is to be expected?
Bert.
Hi Bert,
I changed the end charging voltage to 3.48V this morning. It started continuously charging (no cycling between charging and pending) for a little more than an hour, after which the display showed a similar voltage as you (3.38V) and the display would cycle to charging for a few seconds on and off.
While in pending mode after the full charge, I measured the battery voltage and it was slowly but steadily decreasing (about 0.05V/min). That would explain why after the batteries are fully charged (a longer period of continuous charging), the charger would regularly activate for a short duration to "top off" the batteries that got discharged in the circuit. Is it normal that the batteries discharge slowly with the LiFePO4 off? I don't know but I assume that some of that is due to the continuous battery monitoring.
Ian mentioned that the end charging voltage needs to be higher than the discharge voltage. Therefore, it would seem that it's normal to set the charger to 3.48V in order to get about 3.35V at the battery during discharge.
Paul
I changed the end charging voltage to 3.48V this morning. It started continuously charging (no cycling between charging and pending) for a little more than an hour, after which the display showed a similar voltage as you (3.38V) and the display would cycle to charging for a few seconds on and off.
While in pending mode after the full charge, I measured the battery voltage and it was slowly but steadily decreasing (about 0.05V/min). That would explain why after the batteries are fully charged (a longer period of continuous charging), the charger would regularly activate for a short duration to "top off" the batteries that got discharged in the circuit. Is it normal that the batteries discharge slowly with the LiFePO4 off? I don't know but I assume that some of that is due to the continuous battery monitoring.
Ian mentioned that the end charging voltage needs to be higher than the discharge voltage. Therefore, it would seem that it's normal to set the charger to 3.48V in order to get about 3.35V at the battery during discharge.
Paul
Hi Paul,
When I stiil had all the batteries installed it never started charging again after it got in pending mode. Why should it do the cycling of pending, charging, pending etc with 4 batteries? Maybe @Ian can give an answer to that? Tomorrow I will do some measuring on the batteries itself to see if they all get charged.
Bert.
When I stiil had all the batteries installed it never started charging again after it got in pending mode. Why should it do the cycling of pending, charging, pending etc with 4 batteries? Maybe @Ian can give an answer to that? Tomorrow I will do some measuring on the batteries itself to see if they all get charged.
Bert.
My measurements:
Initial the charge of the used batteries is:
3.295V
3.284V
3.294V
3,296V
After the first cycle of charging to pending at 3.48V i.e. it goes to pending state the result is:
3.348V
3.298V
3.332V
3.339V
After 5 more cycles of pending->charging->pending... the result is:
3.348V
3.298V
3.332V
3.339V
After letting the cycle of pending->charging.. continue for half an hour the result is:
3.350V
3.305V
3.337V
3.351V
After setting the end charge to 3.52V the result after the first charge is:
3.391V
3.329V
3.366V
3.378V
After letting the cycle of pending->charging.. continue for half an hour the result is:
3.393V
3.323V
3.355V
3.367V
The board still continues with the pending->charging.. cycle.
The only reason I can see why it would still do that is because 3.323V is still below 3.35V? I'm just guessing. Maybe someone knows the answer to that?
This is why many big brand audio manufacturers do not recommend users to use batteries for power supply, because the battery power drops to a certain level (such as 90%), there will be problems, and the sound quality will deteriorate. In addition, the battery will start to grow older after being used for a period of time, and the aging degree of each battery is different, which will lead to deterioration of sound quality. The conclusion is that battery-powered may be able to pursue better sound quality, but he will be like a firework: a touch, it will be gone .... wasting money ...
It isn't about a damaged battery. The issui is that when using only 4 batteries instead of 10 batteries the end charging voltage should be increased because the board is callibrated for 10 batteries instead of 4 batteries. After letting it cycle half an hour on end charge of 3.52V and then adjust the end charge to 3.48V seemed to do the trick for me to get in an endless cycle of pending->charging->pending etc.