these cells look interesting would be easier to build with
Apologies for the OT, but I'm close to ordering some batteries for my Soekris, and am wondering if these would be a better choice than the usual AA-style ones for that application...?
Richard
well these are higher capacity so in theory should be better?
its the placement of the tabs i like mostly, they'll make a real tidy battery pack and will be easier to secure in a case
There were notable differences in rating. A123 has Max Continuous Discharge of 70A and Max Pulse Discharge of 120A. The WINA equivalents were 16A and 24A.
Internal Impedance at 1Khz was 6mA for A123 and 13mA (no frequency quoted) for WINA.
I wondered if the superior specs of the 26650 would make an appreciable difference in this application?
There were notable differences in rating. A123 has Max Continuous Discharge of 70A and Max Pulse Discharge of 120A. The WINA equivalents were 16A and 24A.
Internal Impedance at 1Khz was 6mA for A123 and 13mA (no frequency quoted) for WINA.
I wondered if the superior specs of the 26650 would make an appreciable difference in this application?
The internal impedance of a battery is a metric which determines the ability of that battery to deliver instantaneous current - the lower the impedance, the better. The 6mOhm of the A123 cells were the first thing that attracted me to them as I knew from past reading & people's experience with batteries that the lower the internal impedance seemed to correlate to a better the sound (this was when people were using 12V SLA Optima batteries for instance).
I have a suspicion that this also determines the noise of these batteries when delivering current - again the lower the internal impedance, the lower the noise.
So, the 13mOhm of the WN08AH battery, on paper, would seem to be worse but some people will suggest that the wiring from the battery to the circuit will be equivalent to>13mOhm so the internal impedance doesn't matter. Yes, correct but that is missing the other possible benefit of the internal impedance - the lower noise of the chemical reaction taking place inside the battery when delivering current.
So, it may be difficult to judge without trying them, which battery is most suitable for this role as power plant for an amp. Is noise below a certain level important? Is transient current delivery important above a certain speed? Questions which are difficult to answer
Re: It didn't explode....... YET (aka niges amp)
Posted: Mon Jun 20, 2016 6:43 pm
by jrling
Indeed so.
The same company offer Lithium Titanate Oxide cells (LTO) which I had not heard of.
Somewhat pricier than LiFePO4, but durability is excellent. Of course, if float charged, then durability should not be an issue.
The nominal 2.4V voltage appeals to me, as I am looking at a 5V PSU, but I can understand the LiFePO4 provides an excellent 3.3V source.
Re: It didn't explode....... YET (aka niges amp)
Posted: Thu Jun 30, 2016 4:53 pm
by nige2000
batteries arrived earlier than expected
quickly tested on sd card player
there is no difference in comparison to the cylindrical cells as far as sq is concerned on this digital application
so far so good
Re: It didn't explode....... YET (aka niges amp)
Posted: Thu Jun 30, 2016 7:05 pm
by Sligolad
Mind boggles to imagine the amount of current on tap in that box Nige, you could jump start a small country with what you have there:-))
If you need any help with pulling some of these together in the coming weeks drop me a PM.
I will be available at weekends and I have a few weeks off at the end of July.
Looking forward to see these come together.
Re: It didn't explode....... YET (aka niges amp)
Posted: Thu Jun 30, 2016 9:50 pm
by nige2000
Sligolad wrote:Mind boggles to imagine the amount of current on tap in that box Nige, you could jump start a small country with what you have there:-))
If you need any help with pulling some of these together in the coming weeks drop me a PM.
I will be available at weekends and I have a few weeks off at the end of July.
Looking forward to see these come together.
funny i was thinking the same thing when i seen the courier throw it in the door earlier
hes no idea whats in that box!
also because im a child i cant help shorting the cells to see the sparks fly
sure are a lively bunch
i still have to test the revised charging/power management system
when thats sorted it will be full steam ahead
Re: It didn't explode....... YET (aka niges amp)
Posted: Fri Jul 01, 2016 9:18 am
by tony
Scary thought our two best explosive experts working together on that lot
