LifePO4 GBS Amp Hour Testing 2.5v to 3.6v per cell

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  • J.P.M.
    Solar Fanatic
    • Aug 2013
    • 14932

    Originally posted by SunEagle
    I just wanted more information concerning his design but also understood maybe why he did not want to give up the "keys to the kingdom" by answering my questions.
    Looks like Dax put himself in a box with a Hobson's choice. He can keep his proprietary information to himself and risk looking like a charlatan, or share some of it with the intention of establishing or restoring credibility which may cost him some money or lost business when word of his secrets gets out. Some of us may face the same situation and choose to keep out mouth shut on proprietary stuff rather than play "I've got a secret" and look like a jerk or worse. That's one of those things you can't have both ways. Better to not go down that path and simply smile and shut up.

    There is of course a third possibility. Not saying it's so, but there is always the possibility of someone inventing secret scenarios to cover their tracks. Happens all the time.

    Comment

    • smily03
      Member
      • May 2015
      • 83

      The weird thing, to me at least, is that things like chassis wiring methods shouldn't reveal the keys to the kingdom? I could totally see not wanting to release the nitty gritty about balancing methods, system architecture, charging algorithms, etc. But stuff like wiring? How "special" could wiring be, unless you're doing something unsafe? I was kind of surprised at how hostile he got when Mike asked about that...

      I, for one, would love to see something better than lead-acid batteries for applications like this. But, I don't want to get suckered, so when things like this happen, it makes me question the credibility of the other things they've been saying. Which is a shame :/

      Comment

      • J.P.M.
        Solar Fanatic
        • Aug 2013
        • 14932

        Originally posted by smily03
        I, for one, would love to see something better than lead-acid batteries for applications like this. But, I don't want to get suckered, so when things like this happen, it makes me question the credibility of the other things they've been saying. Which is a shame :/
        We'd all like to see progress on the energy storage front. Who/Whatever cracks the energy storage nut will be the next Bill Gates, Sam Walton, or Warren Buffett.

        From a business standpoint, the destroyed credibility when caught in a fraud is probably the worst part. I've seen profitable business relationships it took 10 years to build go completely sour in 10 seconds when half/un truth or B.S. was discovered. Trust is a very fragile thing. It's also what con men try to build and then use as a tool.

        Comment

        • smily03
          Member
          • May 2015
          • 83

          There's a really fragile connection between jumping the gun and letting the "amazing new technology" cat out of the bag too soon, versus running out of funding trying to develop it. Sometimes I wonder if that's what happened with things like the Aquion AHI batteries and their capacity/cycle deratings? It's too bad...

          Comment

          • smily03
            Member
            • May 2015
            • 83

            One thing that's been nagging me (and my ignorance of lithium batteries from a chemical standpoint) is -- isn't the main degradation with lithium-based batteries connected to dendrite growth from charge/discharge cycles? If that's the case, how does micro-cycling batteries affect that?

            Comment

            • SunEagle
              Super Moderator
              • Oct 2012
              • 15124

              Originally posted by smily03
              One thing that's been nagging me (and my ignorance of lithium batteries from a chemical standpoint) is -- isn't the main degradation with lithium-based batteries connected to dendrite growth from charge/discharge cycles? If that's the case, how does micro-cycling batteries affect that?
              Not sure. Lithium based still has a lot of roads to travel hopefully someone will find a great combination of stability, long life and charging technique.

              It seems the "deep pockets" have got the DOE interested in "flow" batteries with a big infusion of money to build and test these liquid batteries for Utility type settings. My guess is that they are way out there in cost and may never come down to anything a homeowner could claim as being cost justified.

              Comment

              • smily03
                Member
                • May 2015
                • 83

                Yeah, that's for sure...as I've been reading about the dendrite stuff, I saw one study[1] that thinks that the dendrites are actually the result of impurities in the lithium, and there are a ton of thoughts about what additives could be, well, added, to help prevent it as well.

                So yeah, time will tell about that, as well as about whether folks with awesome cycle and calendar life are just lucky, or on the cutting edge for the next big thing.

                [1] http://phys.org/news/2013-12-view-de...ries-root.html
                Last edited by smily03; 08-16-2016, 12:55 PM. Reason: Added link

                Comment

                • Sunking
                  Solar Fanatic
                  • Feb 2010
                  • 23301

                  Dax is gone. Yeah!

                  Was a good move Mike, he was a hack and could get someone seriously hurt and the owners could find themselves in court for letting that moron participate.

                  Last edited by Sunking; 08-16-2016, 04:30 PM.
                  MSEE, PE

                  Comment

                  • Sunking
                    Solar Fanatic
                    • Feb 2010
                    • 23301

                    Originally posted by dax
                    However just to amuse you, a 3kw inverter, would never draw 275amp at once or constantly. .

                    You are a Fraud, Hack, and Pretender. You just proved it again. This time was so obvious this others caught it. I spotted you a long time ago when Karrak drug you over to attack me. A 3 Kw inverter operating at 12 volts would draw 300 amps. Up to 600 amps on large motor loads. If you knew Ohm's Law (5th grade math) and efficiency you would know that. Here is proof everyone but Dax will understand. It is simple 5th grade math:

                    Amp = Watt / Volt / Efficiency Factor of System


                    3000 watts / 12 volts / .85 eff = 295 amps moron. Math does not lie, only HACKS and FRAUDS lie. In the USA that would require a minimum 3/0 copper cable to be SAFE, Very very expensive copper cable of $6 per foot. In Aus that is equivalent to 11mm or 85mm^2 copper cable. However used the way you use it over long distances would not work if you tried to pull 3000 watts or 300 amps, not even 100 amps from the batteries. 3/0 can only supply 300 amps up to 5-feet one-way before voltage loss became so severe the inverter would trip off line from under voltage. Just to get 25-feet one way would require 750 MCM copper cable. That cost $15/foot and a 750 MCM is the size of a Man,s wrist and weighs 8-pounds per foot. That is only cable voltage loss, the battery loss will be higher at 6% voltage loss.

                    No one in their right mind who knows anything about power would use 12 volts on a 3 Kw inverter. Not only is it extremely dangerous, but extremely expensive requiring special tooling I know you do not know about to terminate such large cables. 3 Kw demands 48 volt minimum. Commercial systems even know this, you will not find a commercial battery system less than 100 volt battery. 300 to 500 volts being common. At 300 volts a 3 Kw Inverter is only 10 amps on real small wire ran across the house

                    My advice to you is shut up. Because every time you give any details, you give us rope to hang you with. It clearly demonstrates you have no knowledge of what you are doing or why. Batteries and power does not even remotely work like you think it works. It is very simple MATH, and YOU DO NOT ADD UP correctly.
                    Last edited by Sunking; 08-16-2016, 04:17 PM.
                    MSEE, PE

                    Comment

                    • Sunking
                      Solar Fanatic
                      • Feb 2010
                      • 23301

                      Originally posted by jflorey2
                      If it never draws 275 amps it's not being used as a 3kW inverter. If you install a 3kW inverter and downrate it to 1.6kW, great - but in that case might as well just install a good 1.6kW inverter.

                      No, that doesn't mean that. 120V and 240V inverters are readily available with a wide variety of mounting options.

                      The more you post, the more it sounds like your success has been due to luck rather than technical competence and an understanding of the issues involved.. I hope for the sake of your customers that your luck doesn't run out.
                      See we agree sometimes.
                      Last edited by Sunking; 08-16-2016, 04:30 PM.
                      MSEE, PE

                      Comment

                      • Sunking
                        Solar Fanatic
                        • Feb 2010
                        • 23301

                        Originally posted by smily03
                        One thing that's been nagging me (and my ignorance of lithium batteries from a chemical standpoint) is -- isn't the main degradation with lithium-based batteries connected to dendrite growth from charge/discharge cycles? If that's the case, how does micro-cycling batteries affect that?
                        No that is just one of many Failure Mechanisms. Lithium batteries are sensitive and fickel compared to all other batteries. They are not Robust as Pb and Nickel chemistry. They do not play well in hot or cold environments (getting better with LMO), will not tolerate any over discharge, and very sensitive and dangerous to over charge. Other than that and cell voltages they are no different than any other battery.

                        Let's get to it. What you want to know. How do I treat my batteries and not kill them. Ignorance is the number 1 killer of Lithium batteries. Heat issues are the most probable cause of premature failure followed by external elements like short circuits, or faulty equipment.

                        If what the scientist and manufactures were true, lithium ion batteries would last forever if it was only an electrical charge and not chemical. Fact is there is chemical reactions, and it is caused by HEAT. The electrolyte inside is Organic Solvents. Guess what happens to organic material when heated up? It decays. When that happens internal resistance builds up making the battery useless.

                        Good news in a home off-grid battery system, Heat is NOT a big issues, and in most applications not a factor. If they are installed where n temps stay above 40 and below 100 out of the sun with ventilation is OK. EV's are another story.

                        Another way to over heat batteries is with high charge or discharge rates. By HIGH I mean 1C or more. Well if your system is properly designed and sized, you are never going to push 1C for any meaningful time. How many of you plan to use 3 days of electricity in 30 minutes? In a properly sized system you would be charging at C/2 or less. On discharge more like C/10 on PEAK LOADS briefly, otherwise less than C/20. So charge/discharge heat is not much of an issue for most off-grid applications.

                        Now here is where it can be a problem. Over Charge: This is where you need to educate yourself and prevent over charge. Good news is if you are using LiFeP04 aka LFP is the most Tolerant to over charge in the Lithium family. They are the safest of all the lithium batteries.

                        A unique characteristic of lithium batteries is there Internal Resistance vc SOC curve. It is reverse of all other batteries. As it charges up, its internal resistance goes UP. Very desirable but gives us a challenge when charging. Unlike eall other batteries can tolerate excessive over charging. In fact we use that ability. With a Lead Acid battery when one gets fully charged up its resistance is at it lowest and passes current down to lower level batteries thus EQUALIZING them.

                        Not Lithium, current stops when a Lithium cell is Saturated and fully charged up. Its resistance shoots up to stop current flow. If you force it with higher voltage is converted directly as heat. More heat, more current. Thermal Run-Away.

                        The other failure mode is very common among DIY and easy to do especially if you use Balance Boards and rely on automation to do your job. OVER DISCHARGE. LFP will not Tolerate OVER DISCHARGE. It is instant death. Easy to prevent.

                        Not to worry, all of it is manageable. Only thing that cannot be managed today is economics. Today Pb batteries are king of economics and performance. Until lithium battery prices fall to equal or less than PB, then Pb will dominate. The only huge advantage lithium has, energy density, is not required or can be justified for most off-grid systems. One exception I can think of is RV or Boat where weight and space come at premiums.
                        Last edited by Sunking; 08-16-2016, 05:24 PM.
                        MSEE, PE

                        Comment

                        • SunEagle
                          Super Moderator
                          • Oct 2012
                          • 15124

                          Originally posted by Sunking


                          You are a Fraud, Hack, and Pretender. You just proved it again. This time was so obvious this others caught it. I spotted you a long time ago when Karrak drug you over to attack me. A 3 Kw inverter operating at 12 volts would draw 300 amps. Up to 600 amps on large motor loads. If you knew Ohm's Law (5th grade math) and efficiency you would know that. Here is proof everyone but Dax will understand. It is simple 5th grade math:

                          Amp = Watt / Volt / Efficiency Factor of System


                          3000 watts / 12 volts / .85 eff = 295 amps moron. Math does not lie, only HACKS and FRAUDS lie. In the USA that would require a minimum 3/0 copper cable to be SAFE, Very very expensive copper cable of $6 per foot. In Aus that is equivalent to 11mm or 85mm^2 copper cable. However used the way you use it over long distances would not work if you tried to pull 3000 watts or 300 amps, not even 100 amps from the batteries. 3/0 can only supply 300 amps up to 5-feet one-way before voltage loss became so severe the inverter would trip off line from under voltage. Just to get 25-feet one way would require 750 MCM copper cable. That cost $15/foot and a 750 MCM is the size of a Man,s wrist and weighs 8-pounds per foot. That is only cable voltage loss, the battery loss will be higher at 6% voltage loss.

                          No one in their right mind who knows anything about power would use 12 volts on a 3 Kw inverter. Not only is it extremely dangerous, but extremely expensive requiring special tooling I know you do not know about to terminate such large cables. 3 Kw demands 48 volt minimum. Commercial systems even know this, you will not find a commercial battery system less than 100 volt battery. 300 to 500 volts being common. At 300 volts a 3 Kw Inverter is only 10 amps on real small wire ran across the house

                          My advice to you is shut up. Because every time you give any details, you give us rope to hang you with. It clearly demonstrates you have no knowledge of what you are doing or why. Batteries and power does not even remotely work like you think it works. It is very simple MATH, and YOU DO NOT ADD UP correctly.
                          Uhh. Isn't that like kicking a dead horse since he has been banned?

                          Comment

                          • karrak
                            Junior Member
                            • May 2015
                            • 528

                            Originally posted by smily03
                            Yeah, that's for sure...as I've been reading about the dendrite stuff, I saw one study[1] that thinks that the dendrites are actually the result of impurities in the lithium, and there are a ton of thoughts about what additives could be, well, added, to help prevent it as well.
                            The article you posted is about dendrite growth on lithium anodes, all the main lithium ion technologies around at the moment use carbon as the anode to get around this problem. You can get dendrite growth on carbon anodes, it is a result of extended exposure to voltages above 3.65V/cell not cycling.

                            So yeah, time will tell about that, as well as about whether folks with awesome cycle and calendar life are just lucky, or on the cutting edge for the next big thing.
                            All I can say is there are a lot of lucky people around then, just go and look on the Energy Matters and the Endless Spheres forums

                            Simon


                            Off-Grid LFP(LiFePO4) system since April 2013

                            Comment

                            • Mike90250
                              Moderator
                              • May 2009
                              • 16020

                              For all the engineering and high tech stuff in a Tesla car, they still fault and catch fire:
                              -------------- Date: Tue, 16 Aug 2016 07:48:04 -0500 From: "Alister Wm Macintyre " Subject: Tesla Spontaneously Catches Fire! Tesla Spontaneously Catches Fire, Burns Down During Test Drive In France. Not yet explained. There are some clues. http://www.zerohedge.com/news/2016-0...t-drive-france
                              https://electrek.co/2016/08/15/tesla...-drive-france/
                              http://bgr.com/2016/08/15/tesla-mode...os-test-drive/
                              https://www.reddit.com/r/teslamotors...test/?sort=top Earlier there was a Tesla on fire in Norway. A short circuit is the explanation. An automobile spontaneously catching on fire, is not a risk unique to Tesla. Many other auto brand names also experience this surprise hazard. http://www.teslarati.com/tesla-short...s-norway-fire/
                              http://www.vg.no/forbruker/bil-baat-...or/a/23640710/
                              --------------
                              Powerfab top of pole PV mount (2) | Listeroid 6/1 w/st5 gen head | XW6048 inverter/chgr | Iota 48V/15A charger | Morningstar 60A MPPT | 48V, 800A NiFe Battery (in series)| 15, Evergreen 205w "12V" PV array on pole | Midnight ePanel | Grundfos 10 SO5-9 with 3 wire Franklin Electric motor (1/2hp 240V 1ph ) on a timer for 3 hr noontime run - Runs off PV ||
                              || Midnight Classic 200 | 10, Evergreen 200w in a 160VOC array ||
                              || VEC1093 12V Charger | Maha C401 aa/aaa Charger | SureSine | Sunsaver MPPT 15A

                              solar: http://tinyurl.com/LMR-Solar
                              gen: http://tinyurl.com/LMR-Lister

                              Comment

                              • karrak
                                Junior Member
                                • May 2015
                                • 528

                                Originally posted by Sunking
                                3000 watts / 12 volts / .85 eff = 295 amps moron. Math does not lie, only HACKS and FRAUDS lie. In the USA that would require a minimum 3/0 copper cable to be SAFE, Very very expensive copper cable of $6 per foot. In Aus that is equivalent to 11mm or 85mm^2 copper cable.

                                No one in their right mind who knows anything about power would use 12 volts on a 3 Kw inverter. Not only is it extremely dangerous, but extremely expensive requiring special tooling I know you do not know about to terminate such large cables. 3 Kw demands 48 volt minimum.
                                Dax has stated that the cable length from the battery to the inverter is 30cm(1ft), so his cable cost is $12. Hardly a major issue. I am sure his company could afford the appropriate tools. You have no idea whether Dax has the capability or hires someone with the capability to terminate the cables properly.

                                I have a 24V 4kW inverter, Bala has a 24V 3kW inverter and I am sure there are lots more people like us. Peak recorded current from my battery is 245A. Normal heavy load is ~150A and normal load ~5A. Has not burnt the house down yet. The company that made my inverter is over 10 years old and is still in business so must be doing something correctly. Having lead acid batteries is one of the main reasons for not having an inverter with a high current draw as they don't cope with high currents for any length of time. The classic Lead acid battery voltage sag.

                                Simon
                                Off-Grid LFP(LiFePO4) system since April 2013

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