Weak Battery VT75.

[kaide23]

Just get my AWT 26650 4500mAh yesterday. Everything went well this morning, until just now, my battery left half bar at the battery indicator. I was vaping with 0.39ohms SS316L dual coil at 40watts 230degC. After a puff, it show up Weak Battery. I know AWT 26650 written 75A is a hype. Can someone teach me how should I do? I run through this catagory but seems like I am the only that have this problem.... Thanks in advance.

[VapingBad]

Try the test firmware linked in my footer, it reduces the weak battery warnings and flashes the battery icon instead of showing the message.

[kaide23]

Yo man, thanks for the guide. It is my first time using Escribe and DNA chips. After update the firmware, so far so good and the weak battery no longer came up.

[Scarab]

kaide23 said:

After a puff, it show up Weak Battery.

VT75 have a little issue in construction, try this.

[AMDtrucking]

Could somebody explain to me: What is the difference between "Weak Battery"  and flashing battery sign? My DX75 with Sony US26650VT 50A does this at 50% charge, while the flashing battery sign, never flashes.

[dwcraig1]

I believe that the earlier firmware uses weak battery message while the later firmware flashes the battery icon instead.
What is your cell soft cut off set to and what is the battery's standing voltage when this first shows?

[sciha]

Hi, I've charged my AWT IMR 26650 battery to full this morning and was able to vape around 55W without battery blinking.
Just noticed when the battery drains around 3/4 its starts to blink.  Is there an option I can set on escribe to have the battery blinking turn on when its past half the charge of the battery? or something with the initial pulse/preheat that I can adjust.

[Spector NS5 RD]

sciha said:

Hi, I've charged my AWT IMR 26650 battery to full this morning and was able to vape around 55W without battery blinking.
Just noticed when the battery drains around 3/4 its starts to blink.  Is there an option I can set on escribe to have the battery blinking turn on when its past half the charge of the battery? or something with the initial pulse/preheat that I can adjust.

most 26650 batteries are not the best when it comes to vaping 50w and above. you can try a better 26650 battery. i noticed battery mooch is really liking the ijoy 26605. a true 30 amp 26650.

here take a look.......

https://www.e-cigarette-forum.com/forum/threads/ijoy-40a-4200mah-26650-bench-test-results-overrated-but-a-great-30a-battery.764411/

another thing you can try to avoid a premature weak batt message is.....you can see what your "cell soft cutoff" is set to in escribe under the "Mod" tab. you could take it down to 2.68v but no lower than that or you run the risk of having the mod not work correctly (fixable by bringing the CSC back up) .

[AMDtrucking]

dwcraig1 said:

I believe that the earlier firmware uses weak battery message while the later firmware flashes the battery icon instead.
What is your cell soft cut off set to and what is the battery's standing voltage when this first shows?

Hi DGCRAIG1, nice to see you again. You were right, I upgraded firmware and "Weak Battery" doesn't show anymore, my Battery Indicator is flashing instead.  But all 'n all, as much as I vole all seven of my DNA200 devices, I'm very disappointed in DNA75. I have DX75 and VT75. I don't think it's Evolv's fault, I is the lack of a decent 26650 battery on the market today. I've tested MNKE IMR26650 3500mAh 35A, VapPower IMR26650 4200 mAh 40A (bool sh...t), Sony US26650VT 2600mAh 50A. I was able to get 30A and 75 Watts, but only for the first 5 -10 puffs. When my battery is 75% charged and below, the Battery indicator starts flashing and power goes down. I also noticed, that my board overheats quickly. My 75 Watt  Escribe Battery Analyzer was so short, that I can show three of them on one screen: The best performance, I got from Sony US18650VTC5 and VTC6. 26650 batteries were nowhere near them. VapPover 4200 mAh gave me 0.558 Watt/hours (158.9 mAh usable capacity), Sony US26650VT 1.591 W/h (430 mAh usable), Sony US18650VTC5 2.292 W/h (619 mAh) and VapPower 5200 mAh could not reach 75 Watts and failed my test. Sony US26650VT was able to give me full 75 Watts, but not for long. Those are very sad numbers. IMHO. 
 

I'm going to try A123 LiFePo4 battery next. Has anyone tried these batteries? Will DNA75 even support such low Voltage?  Or DNA75 with current batteries is really a 50 Watt device?

[Spammy1982]

Howdy AMDtrucking, 

I also have the VT75 and personally I really like it, but I only vape around 50 watts.  As far as the overheating is concerned I found that crud was accumulating in the threading of the battery compartment, so now I clean the threading with some alcohol every other time I replace the battery and I haven't had the overheating issue.  It's seems to be similar to what tends to happen with tube mech mods (at least the ones I have owned) that start getting hot once the button gets dirty.

Have a good one, 
Sam

[dwcraig1]

So I set out to test my SDNA75 with LG HD2 18650 with my Velocity @75 watts....I eventually gave up (at 34 drags) as it just isn't my thing but here are the screens at the start and my finish. It seemed to do quite well I thought.


But the flashing battery icon was coming soon...@ 2.75 volts.
 

[AMDtrucking]

Is it just me? But in the latest revision of Escribe 1.2 SP3, Battery Analyzer is buggy. It shows up small in upper left corner.

[Rcarter]

AMDtrucking said:

I'm going to try A123 LiFePo4 battery next. Has anyone tried these batteries? Will DNA75 even support such low Voltage?  Or DNA75 with current batteries is really a 50 Watt device?

The DNA200 does officially support LiFePO4, though the DNA75 doesn't come with a LiFePO4 discharge profile built in. While the running voltage is quite low (you'll be in the 2.8-3V range under load in the 50-75W range) because the output curve is so flat you shouldn't be sitting just above the cell cutoff voltage for 95% of the discharge. Definitely worth trying out. 

 

I do have a bit of advice for getting a true 75W out of the DNA75 with fewer issues though. Specifically you will want to try and make sure your resistance is low enough that the board is doing step-down to regulate rather than step-up (boost). Step-down is significantly more efficient, and actually a good deal more accurate and smooth.  This means fewer 'Too Hot' errors, and if you watch the output in escribe you'll notice it's significantly more flat.

It may sounds a little ridiculous at first glance, but if you keep your resistance at or below 0.12ohms you should notice an improvement. It's not too difficult to achieve either. Depending on how you currently build (assuming you're generally using power mode), it might just be as simple as switching to using the same gauge of a lower resistance wire (like SS 316L), or changing from say an 8-wrap coil to a parallel 4-wrap of the same wire to 1/4 the resistance.

[Spector NS5 RD]

Rcarter said:

The DNA200 does officially support LiFePO4, though the DNA75 doesn't come with a LiFePO4 discharge profile built in. While the running voltage is quite low (you'll be in the 2.8-3V range under load in the 50-75W range) because the output curve is so flat you shouldn't be sitting just above the cell cutoff voltage for 95% of the discharge. Definitely worth trying out. 

 

I do have a bit of advice for getting a true 75W out of the DNA75 with fewer issues though. Specifically you will want to try and make sure your resistance is low enough that the board is doing step-down to regulate rather than step-up (boost). Step-down is significantly more efficient, and actually a good deal more accurate and smooth.  This means fewer 'Too Hot' errors, and if you watch the output in escribe you'll notice it's significantly more flat.

It may sounds a little ridiculous at first glance, but if you keep your resistance at or below 0.12ohms you should notice an improvement. It's not too difficult to achieve either. Depending on how you currently build (assuming you're generally using power mode), it might just be as simple as switching to using the same gauge of a lower resistance wire (like SS 316L), or changing from say an 8-wrap coil to a parallel 4-wrap of the same wire to 1/4 the resistance.

you would think that the 75 would be more efficient in buck mode rather than boost. you would be correct that buck tends to be more efficient between the two. but i don't think that applies to this board. actually the opposite applies when dealing with this board. never get the too hot error when output is above battery voltage. with anything .1 and below running at 75w, i get the too hot message on all of my 75 boards, usually after one vape. so if i have a build that requires that type of wattage, and built at a low ohm, i throw it on a dna 200.

[AMDtrucking]

@Rcarter,  I generally vape at TC mode, Nife30 and NiFe48. Therefore low resistance is no problem. My A123 LiFePo4, from eBay, turned out to be fake. I returned it back and ordered one from NKON.NL. It's going to be a while, before it arrives. Meanwhile, I try to use my DNA75 under 50 Watts (Kayfun V5, Rose V3, Marlin etc) and leave my dual coil tanks to six of my DNA200's. All-n-all, I think that DNA75 is a big disappointment due to the lack of good, powerful 26650 batteries, on the market. My Sony US18650VTC4, VTC5 and VTC6 are working better and longer, then VapPower 26650 4200 mAh, MNKE 26650 3500 mAh and Sony US26650VT 2600 mAh. 

 

 

 

[xu7jp4]

DNA 75 works great max @30/35w after weak battery 

This is definitely the first and last

Adios dna75 and welcome dna 200...

Don't buy the dna 60,75,133,167 save your money and buy 200 or 250 with 3 battery not lipo...

That's all

[Spector NS5 RD]

xu7jp4 said:

DNA 75 works great max @30/35w after weak battery 

This is definitely the first and last

Adios dna75 and welcome dna 200...

Don't buy the dna 60,75,133,167 save your money and buy 200 or 250 with 3 battery not lipo...

That's all

this is all dependent on the type of battery you use. 26650, 18650, mah, cdr. If you cannot provide the necessary current the board requires you will get the weak battery message. I use LG HD2C batteries. They work fantastic for the DNA 75, at high wattages. No premature errors.

[xu7jp4]

18650 25r or 26650 mxjo it's the same @50% impossible to have 60w with a coil 0,3 I have message weak battery or check battery... I think it's normal with 1 battery, it's impossible to have 60w @50%...just 40w Now i'm on triade with coil 0.07 @120w and 10% vape on ;-) Definitely DNA 75 is not for high wattage or just 10 seconds ahahahah... Vt75 go to the trash

[Spector NS5 RD]

i will agree that the DNA 75 is power hungry. just know, the way Hcigar implemented the connection from the battery to the board in the VT75 is less than ideal, IMO. as i said, my SMY DNA 75 performs just fine with no "weak battery" messages until the 20%-15% mark, this is when vaping at 65w with a 2 second 75w preheat, punch set to 11. 

instead of trashing your VT75, PM me. 

[dwcraig1]

I tested out my SDMY75 a couple of weeks ago with an Aromamizer  running a couple Kanthal Claptons @75 watts. I use an LG HD2 18650. There was nothing scientific about my test and I noticed nothing unusual battery wise. It appeared to operate as one would expect a single 18650 mod at 75 watts. I thought it lasted much longer than I expected. Just saying.

[diagonal]

At 0.3 ohms and 45 watts both with the mxjo3500mha as well as with the IJoy batteries always the proplem which at 50% at the latest the battery symbol flashes and the power down regulates

[VapingBad]

If that is an 18650 Mxjo it is not surprising, the board is rated at 28 A max, 32 A pulse current and that battery is only 10 A https://www.e-cigarette-forum.com/forum/threads/mxjo-20a-3500mah-18650-bench-test-results-just-another-rewrapped-10a-battery.737524/ 

If it is the 26650 https://www.e-cigarette-forum.com/forum/threads/26650-battery-bench-test-results-and-new-ratings-table.725452/#post-17227385 then the IR with 26650s tends to cause high sag, but I would expect better than your result.

[AMDtrucking]

This just in! I finally, got hold of A123 systems LiFePo4 26650 battery, that is NOT fake. 
I did some tests and, most importantly, vaped most of the day at 75 Watts. IMHO, that battery is our only salvation. It needed some adjustments though. I switched to "Lithium-Polymer" and set the lowest voltage to 2.5V, ran Battery Analyzer and saved the graph:
 
As you can see, from the graph, the battery was charged to full 4.2V. But as soon at the first load was introduced, the battery's voltage dropped to it's normal 3.32V and continued to work flawlessly for pretty long time at 75 Watts. The usable capacity ended up being 7.967 W/h (2400mAh). None of my existing Li-Ion 26650 batteries was able to do that.  VapPower 4200mAh = 158.9mAh (0.588 W/h),  Sony US18650VTC5 = 619.5mAh (2.292 W/h),  Sony US26650VT = 430mAh (1.591 W/h). "Weak Battery" message, is the thing of the past! Too bad, I only bought one of these batteries because I have two DNA75 devices. But I wasn't sure that LiFePo4 was going to do it for me.  Especially, after my first A123 turned out to be FAKE, I bought it on eBay. I've already placed an order for few more HERE. If anyone is interested, I'm placing the content of my CSV battery profile. Just copy it into Notepad and save as .CSV file. Or use my, attached file, if you want.

"Battery Charge (%)","Cell Voltage (V)"
0,3
1.12965977191925,3.04999995231628
2.78649425506592,3.08999991416931
3.86594724655151,3.09999990463257
7.05409812927246,3.16000008583069
13.5810213088989,3.20000004768372
31.5175094604492,3.25
95.1173629760742,3.3199999332428
96.7490921020508,3.33999991416931
98.3808212280273,3.53999996185303
100,4.19000005722046

I forgot to add: According to my measurements, the Internal Resistance of my A123 was 13 m? and I was able, easily, get 50A current from this battery. For that, I made special Voltmeter, that is capable of conducting such current. It is solid SS construction and the wire inside is 12 Gauge. Internals of the spring loaded 510 connector are from Fat Daddy connector.

I also made me a hefty battery holder. For test and charge purposes with spring loaded terminal. 
  

I later, adjusted my discharge graph (manually). I only changed beginning voltage from 4.2V to 3.6V. Also, I changed my low voltage limit from 2.5V to 2.7V, otherwise "Weak Battery" message never shows, even when the mod can't vape anymore.   But I was able to vape Billow V3 with two coils, made out of 26 Gauge NiFe48, with TC, at the actual power of 71W - 75W pretty much all day today. One Billow V3 and a half. All that, on a single battery charge. And I will only charge LiFePo4 battery in my SkyRC MC3000 to 3.6V because, USB will attempt to charge it to 4.2V and that's not good. 

"Battery Charge (%)","Cell Voltage (V)"
0,3
1.12895047664642,3.05000305175781
2.78634595870972,3.08999633789063
3.86725568771362,3.10000610351563
7.0559401512146,3.16000366210938
13.5804328918457,3.19999694824219
31.5175342559814,3.25
95.1170806884766,3.32000732421875
96.747444152832,3.33999633789063
98.3808288574219,3.42441868782043
99.9991836547852,3.59883713722229

 

A123_LiFePo4.zip

[awsum140]

That's really going the "extra mile", AMD!

[Spector NS5 RD]

AMDtrucking said:

This just in! I finally, got hold of A123 systems LiFePo4 26650 battery, that is NOT fake. 
I did some tests and, most importantly, vaped most of the day at 75 Watts. IMHO, that battery is our only salvation. It needed some adjustments though. I switched to "Lithium-Polymer" and set the lowest voltage to 2.5V, ran Battery Analyzer and saved the graph:
 
As you can see, from the graph, the battery was charged to full 4.2V. But as soon at the first load was introduced, the battery's voltage dropped to it's normal 3.32V and continued to work flawlessly for pretty long time at 75 Watts. The usable capacity ended up being 7.967 W/h (2400mAh). None of my existing Li-Ion 26650 batteries was able to do that.  VapPower 4200mAh = 158.9mAh (0.588 W/h),  Sony US18650VTC5 = 619.5mAh (2.292 W/h),  Sony US26650VT = 430mAh (1.591 W/h). "Weak Battery" message, is the thing of the past! Too bad, I only bought one of these batteries because I have two DNA75 devices. But I wasn't sure that LiFePo4 was going to do it for me.  Especially, after my first A123 turned out to be FAKE, I bought it on eBay. I've already placed an order for few more HERE. If anyone is interested, I'm placing the content of my CSV battery profile. Just copy it into Notepad and save as .CSV file. Or use my, attached file, if you want.

"Battery Charge (%)","Cell Voltage (V)"
0,3
1.12965977191925,3.04999995231628
2.78649425506592,3.08999991416931
3.86594724655151,3.09999990463257
7.05409812927246,3.16000008583069
13.5810213088989,3.20000004768372
31.5175094604492,3.25
95.1173629760742,3.3199999332428
96.7490921020508,3.33999991416931
98.3808212280273,3.53999996185303
100,4.19000005722046

I forgot to add: According to my measurements, the Internal Resistance of my A123 was 13 m? and I was able, easily, get 50A current from this battery. For that, I made special Voltmeter, that is capable of conducting such current. It is solid SS construction and the wire inside is 12 Gauge. Internals of the spring loaded 510 connector are from Fat Daddy connector.

I also made me a hefty battery holder. For test and charge purposes with spring loaded terminal. 
  

 

AMD.... at 2.5v set for your cell soft cutoff, have you noticed any strange behavior when the battery is low and you're actually hitting that 2.5v limit cutoff? when i tried a CSC of 2.5v the dna 75 didn't like it, spitting out shorted and other errors when the sag reached that voltage. the hard cutoff is 2.5v so there is no wiggle room left for the board. the dna 75 will not operate below 2.5v and setting my CSC that low caused the board to intermittently reset when trying to vape with a low battery. curious as to your findings when your new lifepo gets seriously low in voltage.