Absorbing Sodium batteries. Capacity gain or worthless?
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- čas přidán 4. 03. 2024
- Today we are having a look at the result of testing sodium batteries with and without absorption. With LiFePO4, we can gain quite a bit of capacity when we give the cell a bit of time during the absorption phase. But how does this look like with Sodium batteries?
I have charged the cell to a specific voltage and measured the capacity from there while discharging. One cycle without absorption, the next cycle with absorption. What capacity do we gain at what voltage when we let sodium absorb?
#sodium #battery #absorption
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GEB Sodium 18650 and prismatic Sodium-ion cells (scroll all the way down an the following website):
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Thanks Andy, all excellent information. Cheers
Very interesting, Andy thanks for all your time for our community to testing these new batteries.
My pleasure!
Andy, I found this video about sodium cells absorption very interesting. Keep up the good work.
Cool, thanks
26 degrees C... Cool... yeah, we definitely use different definitions of the word :)
= 79 degrees F. Yep, that's a cool day anytime between 1st of May and the end of September.
Only 33 degrees C down south of him today. Long pants day, starting to get cool. lol😂
Around 26C is what I set my bedroom AC to during summer. What makes me miserable during summer is humidity and 26C is the highest I can set my AC to if I want it to be remotely effective at dehumidifying. Otherwise, I would prefer to have my room around 30C.
For reference, 26 degrees is full on summer weather here. We might see a few days higher than that, but anything over 30C is rare and considered a heat wave. I can't stand anything over 25C for long. Give me -25C any day though!
Its a cool 8c in the UK at the moment, 26 would be hot, and I'm very glad we don't have -25c.
Well, you can set absorption and float to the same values...like 3.7V
Also, a passive charge balancer can make sense and you can also leave your cheap ative balancer connected the whole time ;)
But still, in a normal solar system, your batteries are fully charged many hours a day...so our LiFePO4 balancing strategies still work perfectly fine as well 😇
P.S.: Thanks for the crazy effort!!!
Thanks for sharing your thoughts. Good answer!
Excellent Andy, a very interesting test that makes me want to build a sodium battery pack and run tests to compare it with my two LiFePo4 units (3004A + 100A). 🙏Thanks for sharing this one more video
Thank you. It's a bit of an investment to build these larger sodium batteries and you may not be able to use them productively.
Great Chart. Thanks!
You're welcome!
Thanks again Andy.
No worries, thank you.
Andy, sign me up for sodium batties!!!
Just reviewing spec sheets. Looks like the Victron Multiplus II will run just fine with these.
The input voltage range of the MultiPlus II is 38 - 66volts
16 Na batteries at 3.95 volts = 63.2 Volts (that's 100 SOC)
16 Na batteries at 2.375 volts = 38 volts (that's less than 10% SOC interpolated from you tests)
So using a Victron Multiplus - it looks to me like you can use 90% of the Sodium battery cells' capacity. Sounds pretty good to me, especially among those who like to cycle at less than 100% SOC.
As discussed in the first sodium battery video😉
I wonder what the output voltage is at the high and lowest batt voltage.
With that voltage range I want to know what happens to the amperage output during a constant high discharge. Say 6kW, as the volts go down the amps go up, how would we live with that without popping things?
@@garys-half-baked-offgrid-dreamIt depends on your inverter and how it handles things. At the moment, there is no equipment out there which can use sodium batteries to its full potential. With our current inverters, we can only use a portion of the usable capacity.
@@OffGridGarageAustralia It's such a disappointing anticlimax, I was excited by the promise of this chemistry.
You got another beer Andy…do not get drunk 😉. Thanks for your amazing video’s with a sense of humour. Weldone mate. Regards from Holland.
Thanks a lot for your feedback and your donation!
Confessions of a hungry mind... I was laying in bed this morning wondering when the next OFF grid Garage video would come out? All Hail the SPAT
Yeah, the test took a while😄
Great research work!
Thank you!
Thanks Andy
Thank you, Wayne!
Hi Andy, very nicely prepared data 👍 I think that a balancer will be much easier to equalise the cells, precisely because of the nicely increasing voltage level run-up😎👍
Yes, in theory it should be easier to balance sodium cells. It will be in the next video soon...
Hey great job and many thanks for this and the previous sodium videos 🎉❤
Love it, its cutting edge news and very very interesting.
Maybe the developers can adjust chemistry accordingly to reduce the voltage delta ...
What is the chemistry exactly? What electrolyte is it? Is the combinatuin sodium iron phosphte existing?
Andy you are perfect my friend with your tests and videos....but as I see the maximum time is a small problem with the numbers and the fingers you show...keep testing and make practice with your hand.... See you again in the next video.
Thank you. More tests to come.
@@OffGridGarageAustralia I know that and I am waiting for this moment.. Andy I think you must leave this 16850 batteries and start the test with the big one new generation 3.2 batteries.. we don't use this in the photovoltaic systems. On this put and the old bms to check if it works or not Maine froind.
Great video. The 80/20 with LFP I'm using to extend the life. I'm wondering going to 100% with Na+ shortens the battery life? I'm wondering if you thought of doing a side by side with lithium-ion versus sodium ion same battery amperage discharge (unless you have charts already..) As an aside there are some videos on CZcams that have done the nail puncture test. No fire they just kind of explode.😮
Thanks Andy. Great work as always. Your tests tell me to stay with LiFePO4. Sodium vrs Li-ion might be a different situation. Sodium appears to have a lower power density but perhaps a safer chemistry compared to Li-Ion?
I thought so too, but is sodium really safer?😉
Thanks for doing this testing and putting it out there. Interesting to see.
You'll have to buy a few of the smallest testers possible and put the cells on constant cycling between different voltages for a year after the balancers - see the lifespan.
I guess with no rare earths they have the potential to be cheap in the future, and if they were 25% the price of LiFePO4, but you could only use the middle 50% of the capacity - but that also meant they would do 10,000 cycles and were even safer then its the still half the cost and double the life. I know that's not the case now, but surely a possibility in the future, for applications where space/weight isnt a concern.
Yeah, long term cycling is a problem as the tester needs to stay connected for that period. And a potential computer to read the data.
If you only use the middle 50%, it would also mean you need twice the capacity to match LiFePO4 atm. The space and weight requirements for batteries would double with Sodium.
Hi Andy, amazing work again. Superinteressting to see the different chemistry performing. I know about your LiFePO4 charge recommodations, but do you think you could perform the same test for LiFePO4 as well? Like charge voltages 3,35-3,65V in steps of 0,05V. Would be extremely interessting and would a great reference to all LiFePO4 users out there! :)
I think I have done this already and found it only works at 3.4V and above. However, 3.4V does not really work as there is not enough voltage delta to start the balancer, so 3.45V turned out to be ideal.
@@OffGridGarageAustralia Thank you for your reply Andy! I am aiming for the Excel graph you've shown in the video. Many people insist on the fact, that a cell is only "full" if it hits 3.65V. But as we know, this is wrong, if we spend some time for absorbtion - or at least it is wrong if we consider 99% SoC also as "full". With the sodiums we have seen two more or less parallel lines: absorbed/non-absorbed capacity. For LiFePO4 I would expect the same parallel graph from 2.5V-3.35V, but the "absorbed"-line should max out at 3.4-3.65V. I think this would be very beneficial to visualize e.g. at your website - even if most of your viewers know this fact already. But as reference to the world it would be superb :)
@@techNick0815 OK, no worries, I'll put this on my list of future videos. Thanks.
@@OffGridGarageAustralia thanks a lot Andy! :)
good stuff Andy. Looks like you would need to use a beefy boost converted with Sibs cos of the steep Volt decline, so as to maintain a reasonable 12 or 24 V level for EV operation. Given that a SiB cas expect 10 year + life. Roll on asap its what we need get the production cost down soonest
Andy, you need to change the 80.000 to 81.000 Herzlichen Glückwunsch!
Yes, I was looking at an electronic board or so, but that's too boring. So, I'll keep printing numbers😄
I think these sodium batteries can be continuously balanced during charging.
The cell voltage determines the SOC and therefore it is perhaps possible to keep the cell voltage the same for all cells with a balancer. All the cells will then reach the required SOC at the same time.
This is however not a normal balancer, but a balancer that uses an average voltage as the balance voltage.
Great video as always i will use your charts 😅😅 i think charging to 3.8 is enough and compatible with all inverters and down to 2.5.
Thank you! That could actually work and also keeps the battery in a healthy voltage range without going into the extremes.
absorbing to a voltage somewhere between always gives extra time and current to load, so its not the absorption that makes the (small) capacity difference, its the amount of current loaded within that longer time...
The interesting part is the "state of charge" depending on endvoltage... thank you
I think we’re going to find less need for balancing. We balance LFP because a few millivolts has a significant impact on SOC. In a series sodium pack, other than the BMS ensuring that no cell goes above 3.95 V or below ~0V, I see little need for balancing, unless the cells are grossly mismatched. My concern for solar storage with these is the large voltage swing between 0-100% SOC. I think this necessitates inverter re-design.
Top Balance, Middle Balance, Bottom Balance - I say let the balancer run.... It will shut itself off when it's happy.
Good thinking. Thanks for sharing.
The Voltage swing can be compensated by using only like 60% of the battery and than have to buy more battery or having better suited inverters. The priece is what matters.
🍺 thanks Andy 😊
No problem 👍
Long story short: for whatever variant of Na-ion cells you got, absorption is effectively the same as float and end-of-charge voltages. Pick whatever SoC you want your system to sit at when "full", look up the corresponding voltage on the curve, set all of your voltages to that, done.
It relates to overpotential voltage vs cell current. For given chemistry, overpotential voltage vs cell current is greater for thicker electrode.
If during charging and discharge tests, you terminate current periodically until cell voltage stops recovering to no load cell voltage you will get direct measurement of overpotential voltage slump (for dischg) or bump (for chrg). You can do this at several points, approx 75%, 50%, and 25% SoC are typically good points. LFP needs 3-5 minutes of rest period of zero current to recover to OCV equilibrium. It would be nice to know what Na-ion is for recovery time. Overpotential gets greater for greater cell current (chg or dischg).
These particular cells have fairly low overpotential. It maybe they are made with thin electrodes. The 200 AH prismatic Na-Ion cell may be different, likely greater, for given C(A) cell current chg/dischg rate. Not all chemistries have symmetrical chg and dischg overpotential voltage vs current. LFP if fairly symmetrical.
There is definitely something happening at about 25% to 35% SoC range where the overpotential rises in that SoC range. It typically means there is some issue with ion migration rate in that SoC range. Na-Ions are significant physically larger than Li-Ions. The graphite negative electrode is called hard graphite, which is more like shale layered graphite, to allow for larger Na ions to infiltrate.
Sodium dendrite growth is an issue with Na-Ion cells and the funky result at 25-35% state of charge may have something to do with the alloying used. Carbon arsenide, nickel antimony. So much for environmentally friendly label.
Interesting! Thanks for sharing.
Nice. I was thinking since victron has its charges sperately (not hybrid) say when the battery is fully charged to where we want n yet there is load n the charger (solar) give power to the inverter and if yet there is extra solar wouldn't that charge the batteries till the bms stops charging. If this happens then the bms won't be the last resort. Or does the charge reduce voltage so that it wouldn't charge the batteries. I not sure if I am clear regarding the question😂
No rain down here, Andy. Charging spare batteries off the main system. But not main for long.
Sunshin this morning, but not for long. More clouds coming in already and temps under 27deg for the next few days. Feels like Melbourne weather🥶
Hi Andy, I have a totally off topic question for. I have a 48V battery pack which has problems. When it discharges the SOC drops down to 0% while the pack voltage remains about 52V. When it charges or is at rest the SOC returns to about 90% and all looks OK then. But as soon as it needs to discharge the SOC drops to 0% again. The pack still delivers the necessary amperes but it seems not ok to me. Additional input, I had a short once at that cell due to my own stupidity and the + pole is very much damaged, could that also be a reason for this behaviour? I hope you will be able to respond! Thanks in advance
I would be interested to see what happens when you connect sodium batteries that are at different states of charge into either a single pack, or packs of different capacity or state of charge together in parallel. You've shown that different states of charge and different capacity doesn't make much difference in LiFePO4 batteries because of the flat charge curve of the cells. Wonder how the linear curves would fare under the same situation!
Something like this will be in the next video...
I have a 500 amp smart shunt connected to 4 100 ah batteries. I want to add batteries but hate to abandon the current shunt and get a larger one. Is it possible to parallel another 500 amp shunt?
Capacity doesn't pay your bills. Energy pays the bills I would like to see a comparison of Energy storage. integral(V*I)=Energy.
Keep up the good work.
All batteries are classified in Ah, not Wh. Ah only uses the current and time. Wh also include the voltage which makes it far less comparable.
Hello Andy,
more Batries or more Panels....What's better?
If you double your batteries, will you get them fully charged on one single sunny day - espacialy during winter?
And how many days per year will more capacity give you a gain?
With my batteries i can get arounnd for two nights and a dark day between. If i double the batteries i will gain around 36 houres.
But in Winter im not getting my batteries fully charged for weeks - doubling them would then not change anything.
In summer they will be discharged at maximum to 65% SOC over night.
So there will be only a gain on some days in Feb and Nov.
Concluding this, my descition was to set up more panels for cloudy conditions and leave the batteries as they are...
I think more panels is the right choice most of the time. You should size your batteries based on demand, which also decreases as you add more solar panels for the worst of days. This is a much better way to go with solar panels being pretty cheap right now.
For the price of a battery you can get a lot of panels. BUT, do you have the space to install them? Not everyone has and is limited by the roof size.
My energy consumption with the Tesla and a potential second EV just around the corner, the plan to connect the whole house to this battery as well as going off-grid with the system, demands more capacity. I can chew through 80% of my battery shelf in one night and if the sun does not shine the next day... well... This would not happen if I'd have a 100kWh battery or more. Sure, I won't fully charge it in winter, but who does???
I think with sodium you can live balancer always on at any voltage, don't need to wait like LiFePo 3,45V
OK, great. I'll show what happens in the next video...
More Salt !! Thanks ❤
Coming!
It sure looks like the balancer could just be left turned on from roughly 50% SOC all the way to 100% SOC. You could charge to just about whatever SOC level you want based on voltage without too many worries. I'll bet sodium battery default settings in BMSs won't do that though... they'll be just as broken as default settings were for LiFePO4, for years and years.
Weather report is in amps now, with XYZ amp-hours expected! Thanks for doing the tests! Interesting interesting.
-Matt
Thanks for all your great comments and support over the years. Much appreciated.
I would say, with this linear curve, you can balance almost at all voltage except near 1.5v. With or without absorption.
That mean, with a frankenstein battery and a high capacity balancer, you can ever make a top and a low balance of your cells. You may be use all the capacity of your differents cells capacity even if i don't know if it will be a good idea for your cells life.
The balancer would still need to be large enough to do a bottom balancing and top balancing with the same pack. with 300Ah and 280Ah in a mix, it needs to move these 20Ah back and forth quickly, depending on the load.
Good answer and thinking.
with the steeper soc charactheristics all those low balance current bms's can actually work, if you can leave balancing on all the time, none of this pulling out of balance on flat part of lifepo4, and with current hardware everybody has to become not discharging below 10-20% clan.
cause the sodium cell would probably go out of inverter range
Got some issues with the info you are giving us. I don't think these small batteries will extrapolate that well to the larger ones. Assuming they are linear in all aspect; still the deviation could be quite large. Also, I am not quite familiar with the price differential within the battery formats. I think the price differential is what is going to do it overall. Knowing the manufactures avarice. Supply and demand will probably be the deciding factor.
The Green Battery 👍 From 🇩🇰 Denmark
Good passive or tiny active balancing WHILE charging seems the way to go. As of the Video from Zerobrain and the conclusion that all above 4V is critical for the electrolyte, i would charge the sodium´s to 3.8v or 3.9V. In combination with LFP i would to the 3.6V to 2.5V setting. It might be a little hard for the LFP ones but the sodium´s are fine. In comparison to the lfp ones i would suggest the sodium´s a shorter cyclelife than the LFP´s. So the "middle" way would be my choice.
You would parallel LFP and sodium? Very brave...
@@OffGridGarageAustraliaWhy not? U can parallel everything if the voltage fits🤪
But don´t be afraid. I think I wouldn´t buy sodium´s instead of LFP´s. The benefits of LFP´s are way to good to choose sodium´s instead.
Wäre auch interessant welche Kapazität die Zelle hat wenn man sie bis zu den angegebenen 0V entlädt und ob diese Zelle nach dem " Transport "( ca 5 Tage ) noch die selbe Kapazität hat wie davor.
Grüße aus Deutschland
I'll do this test later.
It's well known that LiFePo4 should ideally be stored at around 80% capacity and very low discharge or charging to 101% may shorten their lifetime.
How does this compare to the sodium battery type? Is there any data about optimal storage or optimal state for them to be in? If only a certain part of the whole capacity (aka voltage range) was used, should it be either the lowest part, a middle part or the highest part possible?
Viele Grüße und Danke!🇩🇪
Even at 50-60% DoD, these should have a major advantage over LA if you factor in weight, cycle life, and voltage sag. As long at the price is right.
Yeah, OK, in comparison with lead acid, they have an advantage. Voltage is still a hug challenge though.
Heya, absorbing doesn't do much we see. balancing don't thing it is needed but it probable wouldn't hurt. so would like to see that test. yes I know you said no prismatic cell's your gone test still curious what would be the differance against LiFoPo4 prismatic cells and comepaired to the 18650 cell's.
Brrr 26 degrees. Greetings from Belgium
I know, it's so cold!🥶
I have a question I've seen people weld with solar panels..
Anyway how bad is that for the panels?
They deliver power. For what, they don't care.
@@OffGridGarageAustralia That's good thanks for the answer.
From what I understand, since those batteries are not dangerous, so you can use them on all there voltage range. at zero volt it can be recharge and can not burn over voltage. rigth ? I mean I feel better using those king in my house then the other one. for me I use lower setting on lifepo4 to not exceed limits because it's dangerous.
Well, we don't know anything about the safety of these cells. This is just what the marketing says. How safe are they really... watch this space...
I don't think these sodium batteries need to be BMS balanced because of steep voltage curve because as soon as voltage drops in one sharply it would be enough for some current from other ones to flow into it because of higher voltage potential. Sodiums might not be better than lead acid ones but perhaps they have more lifetime cycles in them although I am not sure if anyone proved or debunked this yet.
This would be the case if the cells are in parallel. But if we connect them in series to a 12V battery, you will need a BMS and a balancer.
@@OffGridGarageAustralia let1s see how they balance then with BMS. I reckon should be easy because of steep voltage curve 😁
Time to update your numbers again 😛
Done!
👍😉
Hello Andy! Have you heard anything from 'Peter' lately? I reported errors on the 'Peter' boards but he no longer responds..
Warm greetings from Germany!
Yes, I'm in contact with him. Did you put this on his Github site or through Patreon?
@@OffGridGarageAustraliaI used Patreon. In the meantime he contacted me and provided me with firmware 2.28.
I'll test today to see if the bugs have been fixed.
I wonder how they would compare as replacements to Li-ion 18650 batteries, of the same capacity
This will not work. The voltage is highly different.
@@OffGridGarageAustralia Sorry, I guess I wasn't very clear ... my bad. I'm not talking about replacing a single cell in say, a 7s battery pack ... you're right, that would never work. BMS would freak.
I was talking about a pack made from nothing but the 18650 Sodium cells. Maybe a 4S 12v or an 8S 24V pack.
@@GregOnSummit here again, voltage of the sodium battery is very different. 12V battery starts at 6V linear up to 15.8V. Crazy.
We will do this in one of the next videos.
No need to have an active balancer if the voltage correlates so well with the SOC.
No balancer at all or just not an active one?
When voltage closely aligns with the SOC, opting for a passive balancer rather than an active one is often sufficient. This method leverages the strong voltage-SOC correlation to maintain cell balance effectively and cost-efficiently.
26 degrees in Australia. Sunny and comfy, 26 degrees in the USA 🥶
Hahaha, nice and cool. We enjoy our 26°.
26C is lovely, very close to ideal.
26F …. Not so much 🥶
HI
forgive me if I take advantage
I have a problem with bms JK B2A8S20P-HC
I made a mistake in setting the temperature, the BMS turns on and I can read the screen that indicates "TEMP --200° celsius"....but after a few seconds it turns off, I disconnected the BMS from all the cables power supply and after 3 hours I reconnected the BMS but nothing changes, it shows for a few seconds that everything is ok no errors but the temperature is ---200° C, what can be done? I wrote several emails to jkong but they don't reply.....thanks for your understanding.
michele italy
Best regards
Disconnect the temperature sensor?
@@OffGridGarageAustralia connected or disconnected nothing changes 😪
@@theanimalsfarm5911 No idea, sorry.
Keep emailing them and send messages on Whatsapp as well.
Is there a downside to absorbing? It would seem to me that every extra Wh of capacity is nice to have if there is no added cost or risk in doing so.
Sitting at a high voltage for an extended duration is stressful, and seeing that absorbing at 3.6V still gives less usable capacity than momentarily charging to 3.7V (as an example), there is no gain from absorbing for long duration at a lower voltage (like you'd find for LFP) compared to just charging to the 100% mark and then turning off charging (or going to a lower float value)
@@Stefanfj I agree that it would be better to charge to a higher voltage, but for now that is difficult with Sodium-Ion as a 16S system would go beyond the voltage limits of the available chargers and BMS anyway. So absorbing at this lower voltage would be the way to compensate.
As we have seen in this test, we can absorb at any voltage with these sodium cells.
I'm sure Andy already answered this: Can this cell type if arranged in a 4S-16s configuration omit the BMS?
omitting a BMS is never worth it - BMSes and balancers even make a useful difference in the oldest lead acid batteries - we just didn't have the technology back then and we stopped developing lead acid by the time balancers became cheaper.
BMSes allow you to charge faster, cycle more often and use significantly more of the potentially available capacity without risking damaging a cell with under- or over-voltage and temperature, and even over-current. There is almost no downside to using a BMS except for cost - but since BMSes cost just about the same as a hand full of cells, and they can save those cells within their lifespan, its always worth the cost.
Wouldn't you use a BMS also for current and temperature control?
@@OffGridGarageAustralia It was so cold here this past few months even the toilet and and pipe froze solid. I was standing there with a torch trying to melt through when it came to me.......this is a bad idea! I'm current limited by my inverter, it also shuts down on low voltage, and my smart solar charge controller can clamp down CC/CV at low temp. Im curious if these cells automatically balance in practice.
@@anthonyrstrawbridge the 4 series cells might balance among themselves, but they don't balance with respect to the next set of 4 or the previous set of 4 - there's no way for current to flow in such a way.
Also, sure your inverter cannot draw dangerous currents normally, but if it fails (and they do fail) then it will draw short-circuit type currents and then the BMS protects you so much faster than fuses or circuit breakers ever could - quality BMSes even reduce the fault currents during failures - this makes the resulting explosion rather be a non-event.
@@Stefanfj Temperature design limits of SIB's must be adhered too! Most practically speaking. ✌🏿
Oh man...how long are these Li-ion times past....but its like a bit of a flashback.
You could possible balance at any state of charge - but it would make sense to do this at the end of the charge-voltage i guess
🐸
Great answer, Hannes.
😎
Sodium Battery packs for the current 48V inverters will have to be made with 15 cells. Sodium should be a good option for high voltage inverters though.
Depends on the inverter as we have seen in the first Sodium battery video. 16s can work as well...
💙👊😎
When you build big batteries this could change, doesn't it?
3% Can be a lot when you build a 400 volt battery with high Ah it could be benefitial and better to let them absorb, as long as you have the time for it.
On the other side this could be interesting for a buffer battery which helps to let lithium batteries charge and discharge more constantly, which apears to be favorable?
I would not recommend building a DC HV battery. Far too dangerous.
Secondly, the lithium battery does not need to be charged constantly. It makes no difference to them.
We don't need them sitting at 3.95V for absorption, unless we want ever5 mAh we can get
Good answer.
Hallo Andy. Ich schreibe dir hier weil ich sonst nicht weis wie ich dich sonst erreichen kann. Es geht um den neuen JK BMS. Hab hier bei mir 2 Stück davon. Leider gibt es ein Problem bei dem Pylontech Protokoll. Dort fehlt die Manufaktur Name. Die wird nicht gesendet und aus diesem Grund funktioniert z.b mein Solis rai-3k-48es-5g nicht. Wechselrichter meldet sofort Alarm (BatName-Fail). Hab gestern die neue 15.11 drauf gemacht. Leider ohne Erfolg. Was aber halbwegs funktioniert ist das Victron Protokoll mit meinem Solis WR. Problem hier ist dass die Spannungen RCV nicht übertragen werden. Das nächste Problem beim Pylontech Protokoll ist wenn man zwei BMS parallel schaltet. Beide sind auf 63A Ladegrenze eingestellt. Beim Wechselrichter werden dann 59.8A angezeigt. Das ist ok, aber dann in unregelmäßigen Abständen sendet der JK BMS neuen Wert an den Wechselrichter und der ist 119.7A. 10 Sekunden später geht er wieder auf 59.8A. Also es ist beidem Pylontech Protocol ein Wurm drin. Bitte helfe mir. Hab schon JK selbst angeschrieben aber es kommt keine Antwort. Gruß Peter aus Deutschland.
Thanks for sharing. Nothing I can do because I cannot repeat this test here as I don't have such an inverter to test. Pylontech protocol is always a compromise and may work or may not.
Thanks Andy for the feedback. I can understand that you can't test this. You should only send a message to those who add this company's name to the log. They have now done this with the Victron protocol!!! Version 15.11 says in the log history that the vendor name has been inserted, which you can insert yourself via User Date. Also available on the Internet: (CAN ID: 0x35E) must be PYLON in ASCII format as the manufacturing name. You could just forward this to JK. Thanks.
Andy, winter is coming..😂
I know!🥶
@@OffGridGarageAustralia
This is a balanced... here we wait a spring.. and summer..❤
Which weather we have today?...oh we have 63 Amps outside. Hahahaha
Yes, that's how we classify if it is a good day or not😉
I do not think a balancer will pay for itself wilh this chemistry. But it might be fun to test anyway.
So, no balancing at all? Why do you think the cells won't drift? They may have different internal resistance and therefore different heat loses.
@@OffGridGarageAustraliaI was thinking more in line of passive or periodic manual balancing because of the steep curve making this easier to spot and self-correct over a greater range.
Also the available chargers can not reach the highs or lows of a 16S Sodium battery, so would it really matter that much if one cell added 3.95 volt at the top and another just 3.65 volt?
All of this assumes very low production cost in the near future, making it easier to just add capacity than optimizing and balancing a more expensive set of LFP cells that is better for cars, bikes and portable electronics
Running 20 to 80 percent isn't an issue if the batteries are 500% cheaper and less impact on environment than lifepo.
Q on balancers - this depends on durability and homogeneity of characteristics of separate sodium cells. If homogeneous and durable - balancers.
become redundant.
'48v' battery may need 17 or 18 cells to accommodate the 20% level 2V per cell charge and operate 34V to 67V.
Well, space requirements are an issue for most. If you need double the space for the same capacity, that's not great.
@@OffGridGarageAustralia totally true but the tech is new. Batteries running on one of the most ubiquitous and cheap elements on the planet. Maybe with some rnd they can change the chemical composition to flaten the discharge voltage. I'm a pragmatic idealist and I'm fascinated by your hard work to understand this tech. No doubt somewhere in the world (probably China) bright minds are working on your concerns. I wish it were the West but we are seemingly more interested in pronouns and Love Island.
You might want cell balancing if capacities in the battery are different, I guess. But it's not really as important as for LiFePO4.
So you think in a 4s sodium battery the cells don't drift?
@@OffGridGarageAustralia I suppose the question is whether they might drift predictably (i.e. together) or each one might behave differently, in which case balancing is a must.
But I'm sure you'll tell us soon enough!
7:50 at the background, one of the ZEROes is covered....
Better yet, update it as 81K as of this writing.
Done!
🐸🐸🐸
Moin, moin!
Like# 196? I'm hopeless...
love the continued na batts info!
Glad you made it, Paul!😄
Glad I’m still alive! Where is the 121°f (49.4°c) Sunnyness???
If only you had another chemistry of lithium, say for instance LTO, to do the same test :)
well... 😉
grüße aus deutschland bei -1°C
Ned schoen!
These are early stages. I bet better Chemistries will be out soon. Why condemn sodium when this might not even be the correct sodium battery?
Well, this is exactly what people read on the internet. New battery chemistry will take over... this battery charges 100 times faster and never dies...
All BS, I would say. Only 0.01% of battery inventions actually make it into a small pre-production and even less will be available 10yrs later. Of course they will improve sodium batteries over time, but I just don't see the need for it as long as we have LFP. Sodium will NOT replace LFP as so many articles say.
S.P.A.T. that's German for "late".
Not in this case😄
Sodium still way too expensive per watt maybe in 2028 they will be competitive.
I think it will be even further. If they will replace LFP or NMC at all.
Sodium is only attractive if the price is much lower than lithium batteries.
And if you need a chemistry to work in low temperatures.
How about if we want to electrify everything and get rid of fossil fuels? I think salt instead of Lithium will make a lot more sense as battery storage needs to scale far beyond what is used now.
Yeah like i live in finland so for winter use would be nice for some outside projects@@upnorthandpersonal
There another factor most people don't think about: Space requirement and weight.
Low temperature is only a small advantage as these cells can only handle 0.2C below 0°C.
For me i have small garage system for lights and sockets and its unheated and it has one 500W panel and inverter/charger and couple small agm batteries for 24v but we are 6+months freezing temps so lifepo4 not going to work in winter and agm self discharge is higher than production in middle of winter so sodium would be something to set and forget i dont need high c rates just something to stay alive@@OffGridGarageAustralia