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rmcd Samba Member
Joined: October 29, 2010 Posts: 1348 Location: PNW - its a dry rain.
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Posted: Sat Jul 24, 2021 1:32 pm Post subject: Re: LiFePO4 Batteries: Discussion Thread |
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I ask because the dyisolarforum dude stated pretty explicitly that these batteries degrade above 70F. So, of course, now I'm paranoid. _________________ VW LT40 build. Like a Vanagon but 30% larger in every direction and 40% slower even in metric.
https://www.thesamba.com/vw/forum/viewtopic.php?t=749359&highlight= |
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rmcd Samba Member
Joined: October 29, 2010 Posts: 1348 Location: PNW - its a dry rain.
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ProspectiveOwnergon Samba Member
Joined: May 22, 2020 Posts: 211 Location: SoCal
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Posted: Sat Jul 24, 2021 7:54 pm Post subject: Re: LiFePO4 Batteries: Discussion Thread |
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It's in! What a friggin ordeal! But Imnow compressed left right, and hold down on passenger side of the box. Still some tweaking, but lesson learned....FLIP THE BMS! Can't access the balance lead plug...
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shagginwagon83 Samba Member
Joined: February 07, 2016 Posts: 3786 Location: VA/TN
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Posted: Mon Jul 26, 2021 7:06 pm Post subject: Re: LiFePO4 Batteries: Discussion Thread |
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Very awesome install, well done! _________________ Brandon
"Jo Ann" - '83.5 Westfalia EJ22e w/Peloquin
Instagram @joannthevan |
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fxr Samba Member
Joined: December 07, 2014 Posts: 2300 Location: Bay area CA
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Posted: Thu Jul 29, 2021 12:19 pm Post subject: Re: LiFePO4 Batteries: Discussion Thread |
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I haven't seen this article mentioned before - but forgive me if it's out here in plain sight somewhere!
https://www.solacity.com/how-to-keep-lifepo4-lithium-ion-batteries-happy/
It gives a very good explanation of the whys, wherefores, do's and don'ts of LiFePO4 (LFP) batteries, without being dogmatic.
The summary at the end is pretty good:
Quote: |
To sum up, for long and happy LFP battery life, in order of importance, you should be mindful of the following:
1. Keep the battery temperature under 45 Centigrade (under 30C if possible) – This is by far the most important!!
2. Keep charge and discharge currents under 0.5C (0.2C preferred)
3. Keep battery temperature above 0 Centigrade when discharging if possible – This, and everything below, is nowhere near as important as the first two
4. Do not cycle below 10% – 15% SOC unless you really need to
5. Do not float the battery at 100% SOC if possible
6. Do not charge to 100% SOC if you do not need it |
_________________ Jim Crowther
1984 1.9l EJ22 Westy Wolfsburg Edition
Vespa GTS 300 |
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naturalbill Samba Member
Joined: May 02, 2012 Posts: 5 Location: Saint Petersburg, FL
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Posted: Mon Aug 02, 2021 1:39 pm Post subject: Re: LiFePO4 Batteries: Discussion Thread |
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Have '87 Westy with GoWesty aux battery kit with ProSport12 running lead cells. Just bought 2 GoWesty LiFePO4's thinking all I had to do is swap the batteries out to reap all the benefits of LiFePO4's until I discovered you need a lithium charger. So I get a Victron but got an AC to AC and understand you need a DC to DC. Dumbass me is going crazy. WTF do I do? I now have the incorrect charger apparently with one too many batteries, since I understand (AFTER buying them), the LiFePO4 will NOT serve as a starting battery and is only for auxiliary purposes. I am not interested in solar at this time and I am usually on shore power in State Parks when camping. !. Is it true these can't be used as my lead cells? 2. What is the logical solution to use the LiFePO4's since 2 are too big for the aux bin and I have heard they shouldn't be in parallel anyway. 3. In short, what is the best solution since it looks like I am wed to both these new batteries? Thanks for the indulgence. |
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fxr Samba Member
Joined: December 07, 2014 Posts: 2300 Location: Bay area CA
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Posted: Mon Aug 02, 2021 2:06 pm Post subject: Re: LiFePO4 Batteries: Discussion Thread |
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Did you mean Victron AC to DC? AC to AC makes no sense in this scenario. Please clarify, preferably with a model number.
You can use LFP batteries as starter batteries - they'll happily deliver the current. However, they do NOT like being kept at 100% charge, which is what the alternator will try to do, and probably with a completely incorrect voltage setting. So you'd need to sort that out as well, but it doesn't sound like you're au fait with these things - so bin that idea and get a new lead-acid standard battery instead.
You can also use them in parallel - but you have to ensure you keep both at the same state of charge. This can easily be done by charging them separately to 100% once a year or so. Alternatively, have a switch so you can switch from one to the other.
If you don't need both as your AUX battery, just sell one here on the classifieds - at least then you'll get something back. _________________ Jim Crowther
1984 1.9l EJ22 Westy Wolfsburg Edition
Vespa GTS 300 |
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naturalbill Samba Member
Joined: May 02, 2012 Posts: 5 Location: Saint Petersburg, FL
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Posted: Mon Aug 02, 2021 3:01 pm Post subject: Re: LiFePO4 Batteries: Discussion Thread |
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fxr wrote: |
Did you mean Victron AC to DC? AC to AC makes no sense in this scenario. Please clarify, preferably with a model number.
Thanks Fxr. No, I mistakenly got ACtoAC. Obviously, I'm not a DIY guy, but have a good German tech. My batteries are the GoWesty 50amp, so maybe they would not be enough for starting. I really want to get away from lead cell, thats why i went to LiFePO4's, obviously with extremely half assed or NO knowledge.
You can use LFP batteries as starter batteries - they'll happily deliver the current. However, they do NOT like being kept at 100% charge, which is what the alternator will try to do, and probably with a completely incorrect voltage setting. So you'd need to sort that out as well, but it doesn't sound like you're au fait with these things - so bin that idea and get a new lead-acid standard battery instead.
You can also use them in parallel - but you have to ensure you keep both at the same state of charge. This can easily be done by charging them separately to 100% once a year or so. Alternatively, have a switch so you can switch from one to the other.
If you don't need both as your AUX battery, just sell one here on the classifieds - at least then you'll get something back. |
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fxr Samba Member
Joined: December 07, 2014 Posts: 2300 Location: Bay area CA
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Posted: Mon Aug 02, 2021 3:14 pm Post subject: Re: LiFePO4 Batteries: Discussion Thread |
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What AC to AC did you get? One for transforming 120VAC to 240VAC or what?
Model number PLEASE - then we can suggest if it's potentially useful to you or a Craigslist or Nextdoor candidate.. _________________ Jim Crowther
1984 1.9l EJ22 Westy Wolfsburg Edition
Vespa GTS 300 |
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naturalbill Samba Member
Joined: May 02, 2012 Posts: 5 Location: Saint Petersburg, FL
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Posted: Mon Aug 02, 2021 7:38 pm Post subject: Re: LiFePO4 Batteries: Discussion Thread |
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fxr wrote: |
What AC to AC did you get? One for transforming 120VAC to 240VAC or what?
Model number PLEASE - then we can suggest if it's potentially useful to you or a Craigslist or Nextdoor candidate.. |
Victron Energy Blue Smart IP65 12-Volt 15 amp Battery Charger (Bluetooth)
Touch the image to zoom in
Victron Energy Blue Smart IP65 12-Volt 15 amp Battery Charger (Bluetooth)
Visit the Victron Energy Store
4.7 out of 5 stars 240 ratings | 91 answered questions
Amazon's
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in Battery Chargers by Victron Energy
Price: $147.05 & FREE Returns
Get $50 off instantly: Pay $97.05 $147.05 upon approval for the Amazon Rewards Visa Card. No annual fee.
Size: 12V/15A 120VAC
12V/5A 120VAC
12V/7A 120VAC
12V/10A 120VAC
12V/15A 120VAC
24V/5A 120VAC
24V/8A 120VAC
Brand Victron Energy
Color Blue
Product Dimensions 7.17 x 3.19 x 1.77 inches; 1.98 Pounds
About this item
The Blue Smart IP65 12-Volt 15 amp Battery Charger is the new professional battery charger with built-in bluetooth
The 7-step charging algorithm gets the best out of your battery. The charger gives the battery the power it needs, maintains its health, ensures better performance and a longer life
The Blue Smart IP65 Charger will attempt to recharge a deeply-discharged battery by force-feeding it with a low current. Normal charging will then be resumed as soon as there is sufficient voltage across the battery terminals
The charger comes with both crocodile clips and M8 eyelets, making it easy to connect to the battery, If you wish, you can leave it permanently connected
The Blue Smart IP65 Charger is waterproof and can be used on devices in your workshop and on motor or marine vehicles, such as (classic) cars, boats, yachts and motorbikes |
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xoo00oox Samba Member
Joined: February 11, 2010 Posts: 2671 Location: East Nassau, NY
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Posted: Tue Aug 03, 2021 5:29 am Post subject: Re: LiFePO4 Batteries: Discussion Thread |
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That is an 110/120V-AC to 12V-DC charger that you got, it should be fine for charging that battery. |
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fxr Samba Member
Joined: December 07, 2014 Posts: 2300 Location: Bay area CA
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Posted: Tue Aug 03, 2021 9:15 am Post subject: Re: LiFePO4 Batteries: Discussion Thread |
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naturalbill wrote: |
fxr wrote: |
What AC to AC did you get? One for transforming 120VAC to 240VAC or what?
Model number PLEASE - then we can suggest if it's potentially useful to you or a Craigslist or Nextdoor candidate.. |
Victron Energy Blue Smart IP65 12-Volt 15 amp Battery Charger (Bluetooth) |
That's fine for charging those GW lithium batteries from shore power. _________________ Jim Crowther
1984 1.9l EJ22 Westy Wolfsburg Edition
Vespa GTS 300 |
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naturalbill Samba Member
Joined: May 02, 2012 Posts: 5 Location: Saint Petersburg, FL
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Posted: Tue Aug 03, 2021 11:23 am Post subject: Re: LiFePO4 Batteries: Discussion Thread |
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So would it be best to keep the Victron or send it back and get the Renogy 40AMP DC to DC for the best installation? My original goal was to trash the lead acids and simply replace them with the LiFePO4's, having NO idea being a non-DIY this is a lot more involved than that. So, is that possible or do I need to keep the ProSport for a lead-acid starting battery and use whichever appropriate charger for the lithium and just use that or those for the slaves? Thanks for indulging this non-motor head on this very learned site.
fxr wrote: |
naturalbill wrote: |
fxr wrote: |
What AC to AC did you get? One for transforming 120VAC to 240VAC or what?
Model number PLEASE - then we can suggest if it's potentially useful to you or a Craigslist or Nextdoor candidate.. |
Victron Energy Blue Smart IP65 12-Volt 15 amp Battery Charger (Bluetooth) |
That's fine for charging those GW lithium batteries from shore power. |
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fxr Samba Member
Joined: December 07, 2014 Posts: 2300 Location: Bay area CA
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Posted: Tue Aug 03, 2021 5:26 pm Post subject: Re: LiFePO4 Batteries: Discussion Thread |
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If you read through this whole thread you'll get some ideas. What I would do if I was in your situation and didn't want solar:
If you can, get your money back for the Victron.
Buy a lead-acid battery for your starter battery. It should last 7-10 years.
If you can't send back one of the GW LFP batteries, consider selling here on the classifieds - at least you'll get something back for that.
Buy a Renogy dc-dc charger - the 20A one will be fine for you if you are absolutely convinced you'll never need or wish for solar. https://www.renogy.com/12v-dc-to-dc-on-board-battery-charger/ _________________ Jim Crowther
1984 1.9l EJ22 Westy Wolfsburg Edition
Vespa GTS 300 |
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naturalbill Samba Member
Joined: May 02, 2012 Posts: 5 Location: Saint Petersburg, FL
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Posted: Tue Aug 03, 2021 6:55 pm Post subject: Re: LiFePO4 Batteries: Discussion Thread |
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Thank you so much Jim. It’s been a learning experience. Your knowledge has been a big help.
Bill
fxr wrote: |
If you read through this whole thread you'll get some ideas.
What I would do if I was in your situation and didn't want solar:
If you can, get your money back for the Victron.
Buy a lead-acid battery for your starter battery. It should last 7-10 years.
If you can't send back one of the GW LFP batteries, consider selling here on the classifieds - at least you'll get something back for that.
Buy a Renogy dc-dc charger - the 20A one will be fine for you if you are absolutely convinced you'll never need or wish for solar. https://www.renogy.com/12v-dc-to-dc-on-board-battery-charger/ |
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dobryan Samba Member
Joined: March 24, 2006 Posts: 16473 Location: Brookeville, MD
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Posted: Thu Aug 05, 2021 5:53 am Post subject: Re: LiFePO4 Batteries: Discussion Thread |
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I am looking to set up my charging systems so that I do not keep the LiFEPO4 battery at 100% when it is sitting for extended periods when I am not traveling.
I am using this as a reference.
https://www.solacity.com/how-to-keep-lifepo4-lithium-ion-batteries-happy/
<<<<<<<<<<<<<<<<<<<<< Quoted from the above link...<<<<<<<
Charge Voltage Needed
So what Voltage is enough to get those ions moving? A little experimenting shows that 13.6 Volt (3.4V per cell) is the cut-off point; below that very little happens, while above that the battery will get at least 95% full given enough time. At 14.0 Volt (3.5V per cell) the battery easily charges up to 95+ percent with a few hours absorb time and for all intents and purposes there is little difference in charging between 14.0 or higher Voltages, things just happen a little faster at 14.2 Volt and above.
Lithium-ion cell
Lithium-ion cell structure
Bulk/Absorb Voltage
To summarize this, a bulk/absorb setting between 14.2 and 14.6 Volt will work great for LiFePO4! Lower is possible too, down to about 14.0 Volt, with the help of some absorb time. Slightly higher Voltages are possible, the BMS for most batteries will allow around 14.8 – 15.0 Volt before disconnecting the battery. There is no benefit to a higher Voltage though, and more risk of getting cut of by the BMS, and possibly damage.
Float Voltage
LFP batteries do not need to be floated. Charge controllers have this because lead-acid batteries have such a high rate of self-discharge that it makes sense to keep trickling in more charge to keep them happy. For lithium-ion batteries it is not great if the battery constantly sits at a high State-Of-Charge, so if your charge controller cannot disable float, just set it to a low enough Voltage that no actual charging will happen. Any Voltage of 13.6 Volt or less will do.
Equalize Voltage
With charge Voltages over 14.6 Volt actively discouraged, it should be clear that no equalize should be done to a lithium-ion battery! If equalize cannot be disabled, set it to 14.6V or less, so it becomes just a regular absorb charge cycle.
Absorb Time
There is a lot to be said for simply setting the absorb Voltage to 14.4V or 14.6V, and then just stop charging once the battery reaches that Voltage! In short, zero (or a short) absorb time. At that point your battery will be around 90% full. LiFePO4 batteries will be happier in the long run when they do not sit at 100% SOC for too long, so this practice will extend battery life. If you absolutely have to have 100% SOC in your battery then absorb will do that! Officially this is reached when the charge current drops to 5% – 10% of the Ah rating of the battery, so 5 – 10 Amp for a 100Ah battery. If you cannot stop absorb based on current, then set absorb time to about 2 hours and call it a day.
>>>>>>>>>>>>>>>>>>>
It looks like I need to set up my chargers for zero absorb time. And check the bulk/absorb charge voltage settings
I'll post more here when I get into the programming of my Victron chargers.
Solar
DC/DC
AC/DC
Advice from those that are knowledgeable is very welcome. _________________ Dave O
'87 Westy w/ 2002 Subaru EJ25 and Peloquin TBD
"To travel hopefully is a better thing than to arrive." Robert Louis Stevenson
MD>Canada>AK>WA>OR>CA>AZ>UT>WY>SD
https://www.thesamba.com/vw/forum/viewtopic.php?t=620646
Building a bus for travel in Europe (euroBus)
https://www.thesamba.com/vw/forum/viewtopic.php?t=695371
The Western Syncro build
https://www.thesamba.com/vw/forum/viewtopic.php?t=746794 |
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Vanuber Samba Member
Joined: February 16, 2020 Posts: 410 Location: Virginia
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Posted: Thu Aug 05, 2021 11:46 am Post subject: Re: LiFePO4 Batteries: Discussion Thread |
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dobryan wrote: |
I am looking to set up my charging systems so that I do not keep the LiFEPO4 battery at 100% when it is sitting for extended periods when I am not traveling.
It looks like I need to set up my chargers for zero absorb time. And check the bulk/absorb charge voltage settings
I'll post more here when I get into the programming of my Victron chargers.
Solar
DC/DC
AC/DC
Advice from those that are knowledgeable is very welcome. |
I have been wondering this myself and have similar Victron chargers. I will be following your findings. _________________ '85 Westfalia 1.9L
'72 BMW R75/5
'71 BMW R75/5
'02 Subaru Forester 2.5L |
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fxr Samba Member
Joined: December 07, 2014 Posts: 2300 Location: Bay area CA
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Posted: Thu Aug 05, 2021 5:42 pm Post subject: Re: LiFePO4 Batteries: Discussion Thread |
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I have a switch that can disconnect the panels completely should I so wish, and a switch (breaker) to disconnect from the alternator. I also set the max voltage to 14.4V. With the parasitic drain from the radio and a roof vent fan coming on automatically when the temperature inside goes >90°F, the battery doesn't get overcharged, very rarely gets near 100% and so far seems very happy sitting in the driveway.
I might reduce the max voltage to 14.0V and leave the solar on and alternator disconnected unless we're camping. Still early days for this setup! _________________ Jim Crowther
1984 1.9l EJ22 Westy Wolfsburg Edition
Vespa GTS 300 |
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Crooked Designer Samba Member
Joined: March 22, 2018 Posts: 308 Location: Chicago, IL
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Posted: Fri Aug 06, 2021 8:54 am Post subject: Re: LiFePO4 Batteries: Discussion Thread |
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That is a pretty great read. "Keep the battery temperature under 45 Centigrade (under 30C if possible) – This is by far the most important!!"
Seems like avoiding high temps is a case for mounting LiFePO4 batteries outside / under the van.. I've only seen huge lead acid batteries done this way in the past and operating temperature (cold) was always the concern there. Anyone doing this with LiFePO4 aux batteries? 45C is 113F and I've definitely seen interior temps hit that and higher. Can't imagine it's that hot in the shade outside and under the van. (at least in the midwest. I'm sure you desert dwelling people have other things to say about this.) 30C is 86F, which seems not possible for any summer travel in the USA without AC. _________________ '85 Westy full camper, Subaru 2.5L, 5 speed SubiGears + 5speedbus shifter kit |
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dobryan Samba Member
Joined: March 24, 2006 Posts: 16473 Location: Brookeville, MD
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