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Battleborn White Paper Discussing LiFePO4 Cold Temp Charging/Discharging Test Results

Will Prowse

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Hmmm.

This is kinda rubbish. This really feels like just a bunch of distraction from, "you can't charge our batteries when it's cold.'

Read the page. WAY more marketing than meaningful science, and I can't say I learned anything at all. Read the white paper in the process of skimming it to validate a few of the claims on the page.

"The batteries were discharged at the industry recommended 50% depth of discharge. The LiFePO4 batteries were discharged at a rate of 11.8V and the AGM lead acid batteries were discharged at a rate of 12.2V. "

"Rate" of 11.8V and 12.2V? Really? At least they didn't say that in the whitepaper itself. MOAR PROOFREADING GEYEZ!!!!

Calling 12.2V the 50% DoD point for AGM is absurdly ridiculous. Almost as ridiculous as calling a voltage a rate. They did this even after "explaining" Peukert KNOWING the 50% point moves on that basis alone... not to mention that guy... Ohm... and his law and stuff.

After the first discharge in the freezer, they were charged IN the freezer. There's no mention of temperature compensation for the AGM. That bugger would need to go to almost 16V for a full charge in the lowest of those temperatures.

This was DESIGNED to make the AGM look bad based on the absurd notion that an AGM is at 50% SoC at 12.2V "as recommended by the manufacturer" FOR RESTING VOLTAGES!

A well executed test would have run the battery to 10.5V and then CALCULATED the 50% capacity from the 100% discharge.

I am not impressed at all.

I guess experimental design isn't important when it's hard to sell batteries for $750/kWh.

I'm not anti-BB after this, but the guy that designed this experiment needs to learn about the scientific method.

I'm not anti-LFP either. I have about 7kWh of it, 44kWh of Lithium NMC, 26kWh of NiMH, 20kWh of FLA and 5 kWh of AGM. I LOVE batteries (and my wife tolerates some serious shit), and no. I'm not counting the couple dozen 12V batteries for autos/RV/etc., stuff (I have 23 forms of transportation that require one or more 12V).
 
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A well executed test would have run the battery to 10.5V and then CALCLATED the 50% capacity from the 100% discharge.
Would you then expect to see drastic changes in the histograms they presented? I'm not sure their conclusion statements would be invalidated, but perhaps they should try again...'double-down', as it were.

edit: I don't like this sentence, though: "Though the battery banks were comparable in ampere-hour size, the deliverable energy of the lead acid at the high discharge rates and lower temperatures rendered this battery bank nearly useless when a protective low-voltage threshold is implemented in the electrical."
This should be revised and clarified, imho.
 
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Liked then unliked.

Hmmm.

This is kinda rubbish. This really feels like just a bunch of distraction from, "you can't charge our batteries when it's cold.'

Read the page. WAY more marketing than meaningful science, and I can't say I learned anything at all. Read the white paper in the process of skimming it to validate a few of the claims on the page.

"The batteries were discharged at the industry recommended 50% depth of discharge. The LiFePO4 batteries were discharged at a rate of 11.8V and the AGM lead acid batteries were discharged at a rate of 12.2V. "

"Rate" of 11.8V and 12.2V? Really? At least they didn't say that in the whitepaper itself. MOAR PROOFREADING GEYEZ!!!!

Calling 12.2V the 50% DoD point for AGM is absurdly ridiculous. Almost as ridiculous as calling a voltage a rate. They did this even after "explaining" Peukert KNOWING the 50% point moves on that basis alone... not to mention that guy... Ohm... and his law and stuff.

After the first discharge in the freezer, they were charged IN the freezer. There's no mention of temperature compensation for the AGM. That bugger would need to go to almost 16V for a full charge in the lowest of those temperatures.

This was DESIGNED to make the AGM look bad based on the absurd notion that an AGM is at 50% SoC at 12.2V "as recommended by the manufacturer" FOR RESTING VOLTAGES!

A well executed test would have run the battery to 10.5V and then CALCLATED the 50% capacity from the 100% discharge.

I am not impressed at all.

I guess experimental design isn't important when it's hard to sell batteries for $750/kWh.

I'm not anti-BB after this, but the guy that designed this experiment needs to learn about the scientific method.

I'm not anti-LFP either. I have about 7kWh of it, 44kWh of Lithium NMC, 26kWh of NiMH, 20kWh of FLA and 5 kWh of AGM. I LOVE batteries (and my wife tolerates some serious shit), and no. I'm not counting the couple dozen 12V batteries for autos/RV/etc., stuff (I have 23 forms of transportation that require one or more 12V).
Good point about LVD. I agree.

Voltage curve of LiFePO4 is much different than Pb battery as well. This would change LVD as well.
 
Would you then expect to see drastic changes in the histograms they presented? I'm not sure their conclusion statements would be invalidated, but perhaps they should try again...'double-down', as it were.

edit: I don't like this sentence, though: "Though the battery banks were comparable in ampere-hour size, the deliverable energy of the lead acid at the high discharge rates and lower temperatures rendered this battery bank nearly useless when a protective low-voltage threshold is implemented in the electrical."
This should be revised and clarified, imho.

As one would expect with known issues related to both cold temp capacity and reduced capacity with high current, the conclusions would be correct in direction, but the magnitude would be notably muted.

Furthermore, lead acid batteries intended for power systems often have additional data available that include low temp capacity and a logarithmic charge for Peukert effects.

Here's an excerpt from the T-1275 datasheet (familiar with these. I have 12):

1602737833419.png

At 80A, you'll get an estimated 70 minutes. Note that while the chart is an estimate, this battery has a 70 minute 75A rating, so lets say 65 minutes. At 15°F, you'll get about 55%.

Combining the two, a 150Ah battery will have a 87 * .55 = 48Ah capacity. Reduce that to 24Ah for the 50% rule.

24Ah out of 150Ah sucks, but it's better than 0, which is what you get every 2nd, 3rd, 4th, etc., discharge with LFP, but at least FLA/AGM can give you 24Ah each time you charge it at 15°F (absorp at 15.86V).

Note that while I'm using a 150Ah battery as an example, this single battery capacity is LESS than the two paralleled batteries they used (210Ah).

This is all just known stuff. BB presented it in a biased way with a poor experimental design looking to diminish their disadvantage associated with cold charging. Had it been just fluff on a webpage, I wouldn't care much, but to develop a "whitepaper" and attempt to come across as scientific is disingenuous.

I'll go away now. :)
 
Hmmm... can't believe no one commented on their video about this... maybe someone is deleting comments? Let's see if this one stays... saved here just in case...


I have never seen so slanted and ignorant test methods.

This is really pathetic.I can't believe no one has commented on this. This was a horribly executed test. It is not a white paper. It is marketing drivel. Battleborn knows better - with absolutely certainty - that using open circuit RESTING voltage of 12.2V for lead acid termination is completely absurd discharge termination criteria. The discharge should have continued to 10.5V and the resulting capacity halved to give a true representation of anticipated performance. And guess what... when you NEED that extra capacity, using 100% of it isn't going to measurably reduce its cycle life with OCCASIONAL use.

Claiming that you can't put charge into a lead acid at low temperature is equally absurd. It's like you don't understand how lead acid batteries work - they require TEMPERATURE COMPENSATION to properly charge, i.e., at lower temperatures, you charge to HIGHER voltages SAFELY. This requirement is clearly stated with specific data given on any quality lead-acid battery. At freezing, a typical AGM needs to be charged at least 0.45V higher than it's 25°C absorption voltage. Victron inverter/chargers and MPPT that you sell have this feature built in, so you can't claim you didn't know about it.

A typical lead acid will yield about 60% of rated capacity at about 20°F - varies between types and manufacturers, but it's a good approximation... SO rather than provide a valid test that shows you would get ABOUT 126Ah from a 210Ah AGM battery bank, they create an absurd test that yields... 0.64Ah while the LFP produces 154Ah - still notably superior to cold AGM, but at least it's honest... but of course, you couldn't recharge them, eh?

I actually love LFP. I have about 6kWh of it. Great chemistry with excellent capabilities for deep cycle power applications (suck for starting vehicles). This experiment could have been done meaningfully by utilizing decades known characteristics of lead acid batteries rather than making horrifically amateurish and downright ignorant assumptions horribly flawed test methodology.

You could have used this test to demonstrate the meaningful differences that you incorrectly claim as attributable to increased resistance. You could have demonstrated that due to the higher operating voltage of LFP and higher resistant of lead acid, for a given power output, you have higher current and consume more Ah with lead acid.

Superior performance would still have been demonstrated in every test. It just wouldn't look like marketing people did it instead of people with technical competence.

You guys charge a massive premium for your product. You should at least attempt to appear technically competent and not just producing data to justify your price premium.

This could have been an amazing exercise that demonstrates MULTIPLE advantages of LFP over lead acid. You just wanted to keep your thumb on the scale.
 
There is one point I flat I know is wrong on that video and bullcrap when it has to do with charging lead acid at low temps. I have charged my 24v lead acid deep cycle bank at -2F just fine.

Also that last part where he claims the lead acid makes no power below freezing I don't get either. I never "tested" to see how much power my lead acid banks made at low temps since I was more worried about the crappy weather itself and panels not putting out that much but they never stopped powering my home. I don't remember what amp draw I was doing back then but again the house kept running at -2F so saying lead acid puts out no power or almost no power can't be right. I just don't have hard numbers as to how much they actually put out but I know they work to some extent since the stuff in my house kept functioning.
 
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Hmmm... can't believe no one commented on their video about this... maybe someone is deleting comments? Let's see if this one stays... saved here just in case...


I have never seen so slanted and ignorant test methods.

This is really pathetic.I can't believe no one has commented on this. This was a horribly executed test. It is not a white paper. It is marketing drivel. Battleborn knows better - with absolutely certainty - that using open circuit RESTING voltage of 12.2V for lead acid termination is completely absurd discharge termination criteria. The discharge should have continued to 10.5V and the resulting capacity halved to give a true representation of anticipated performance. And guess what... when you NEED that extra capacity, using 100% of it isn't going to measurably reduce its cycle life with OCCASIONAL use.

Claiming that you can't put charge into a lead acid at low temperature is equally absurd. It's like you don't understand how lead acid batteries work - they require TEMPERATURE COMPENSATION to properly charge, i.e., at lower temperatures, you charge to HIGHER voltages SAFELY. This requirement is clearly stated with specific data given on any quality lead-acid battery. At freezing, a typical AGM needs to be charged at least 0.45V higher than it's 25°C absorption voltage. Victron inverter/chargers and MPPT that you sell have this feature built in, so you can't claim you didn't know about it.

A typical lead acid will yield about 60% of rated capacity at about 20°F - varies between types and manufacturers, but it's a good approximation... SO rather than provide a valid test that shows you would get ABOUT 126Ah from a 210Ah AGM battery bank, they create an absurd test that yields... 0.64Ah while the LFP produces 154Ah - still notably superior to cold AGM, but at least it's honest... but of course, you couldn't recharge them, eh?

I actually love LFP. I have about 6kWh of it. Great chemistry with excellent capabilities for deep cycle power applications (suck for starting vehicles). This experiment could have been done meaningfully by utilizing decades known characteristics of lead acid batteries rather than making horrifically amateurish and downright ignorant assumptions horribly flawed test methodology.

You could have used this test to demonstrate the meaningful differences that you incorrectly claim as attributable to increased resistance. You could have demonstrated that due to the higher operating voltage of LFP and higher resistant of lead acid, for a given power output, you have higher current and consume more Ah with lead acid.

Superior performance would still have been demonstrated in every test. It just wouldn't look like marketing people did it instead of people with technical competence.

You guys charge a massive premium for your product. You should at least attempt to appear technically competent and not just producing data to justify your price premium.

This could have been an amazing exercise that demonstrates MULTIPLE advantages of LFP over lead acid. You just wanted to keep your thumb on the scale.

Yep, there are still 0 comments on their video. That video is 3 years old. I think I might know what is going on though (I have a youtube channel). If I recall, when you upload a video to youtube you can choose to allow all comments, allow no comments (it will say "comments turned off") or all comments go into a queue for moderation. If one were to simply never check on (deliberate or not) the queue, then none of us would ever see the comments. They need to be approved first. I may have that wrong in my memory, but I'm pretty sure that's right (famous last words!)

Which would be a great way to not be a platform for all the naysayers to spit on you on your platform. Hmm...I wonder why they'd have to do that? Eventually no one but people with more money than brains will buy their products and that's their business plan, but eventually the ratio of people with more money than brains is going to go down. Look at some of the millennials. They're smart enough than to work for a system that doesn't support what they believe in, so they get by with less and money is less of a drive. It's when one "takes one for the team" and suffers to stand up for what they believe is right.
 
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