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Lifepo4 battery

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Printed Date: 15 Dec 2019 at 6:29am
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Topic: Lifepo4 battery
Posted By: Olddawgsrule
Subject: Lifepo4 battery
Date Posted: 10 Nov 2019 at 9:20am
The deals out of China start tomorrow and 1 day only. I'm watching for a deal on a Lipo4 battery and here's the one topping the list.

This one takes a 14.6v charge (as we'd hope for) and normal operating voltage of 12.8 (also what we're looking for). Be careful of one that charge 12v and operate 12v, those typically are rated 12v to 9v discharge.. Being we'd only get about 30-40% usage from them.

This one is 80ah and charges at 10amps. I'd have to setup charging accordingly. Build in balance charging and wall-wort charger included. Price shown is shipped.

http://www.aliexpress.com/item/4000270680508.html?spm=a2g0o.productlist.0.0.1d4a4a70aVBKrC&algo_pvid=923f6d5a-cfff-485b-9161-451323a5196c&algo_expid=923f6d5a-cfff-485b-9161-451323a5196c-29&btsid=5873e86a-39fc-414f-87c6-1057c158226c&ws_ab_test=searchweb0_0,searchweb201602_9,searchweb201603_55 - http://www.aliexpress.com/item/4000270680508.html?spm=a2g0o.productlist.0.0.1d4a4a70aVBKrC&algo_pvid=923f6d5a-cfff-485b-9161-451323a5196c&algo_expid=923f6d5a-cfff-485b-9161-451323a5196c-29&btsid=5873e86a-39fc-414f-87c6-1057c158226c&ws_ab_test=searchweb0_0,searchweb201602_9,searchweb201603_55


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2018 RPOD 182g 'Lily'
2017 Tacoma SR5
Life is good!

https://olddawgsrule.wixsite.com/website - Spirit of Adventure WebSite



Replies:
Posted By: Olddawgsrule
Date Posted: 10 Nov 2019 at 9:25am
This is the other one I'm watching.

http://www.aliexpress.com/item/32976417259.html?spm=a2g0o.productlist.0.0.4558e3b4fDRbHr&algo_pvid=8f74ace1-87d3-4363-acc9-1beb9d88a615&algo_expid=8f74ace1-87d3-4363-acc9-1beb9d88a615-12&btsid=2baa9432-0c21-48d5-9f86-b2b5d15d32f1&ws_ab_test=searchweb0_0,searchweb201602_9,searchweb201603_55 - http://www.aliexpress.com/item/32976417259.html?spm=a2g0o.productlist.0.0.4558e3b4fDRbHr&algo_pvid=8f74ace1-87d3-4363-acc9-1beb9d88a615&algo_expid=8f74ace1-87d3-4363-acc9-1beb9d88a615-12&btsid=2baa9432-0c21-48d5-9f86-b2b5d15d32f1&ws_ab_test=searchweb0_0,searchweb201602_9,searchweb201603_55


-------------
2018 RPOD 182g 'Lily'
2017 Tacoma SR5
Life is good!

https://olddawgsrule.wixsite.com/website - Spirit of Adventure WebSite


Posted By: DavMar
Date Posted: 10 Nov 2019 at 6:25pm
My Lord Olddawgsrule for those prices I can buy three lead acid batteries for every one of those. Yes, I know they have more amp hours and discharge rate but my question is does it make economic sense over lead acid or even sealed glass mat batteries? I'm just wondering what is the advantage now of spending 3 times the money for lithium battery? Educate me please!


-------------
Dave & Marlene J with Zoey the
wonder dog.
2017 Rpod 180
2016 Toyota Tacoma SR5 4x4
Lexington, NC


Posted By: crazycoyote
Date Posted: 10 Nov 2019 at 6:39pm
I quit buying directly from China, I don't trust dealing with them. In June I ordered 2 electric folding Trikes at $199.00 each, and waited 4 weeks for delivery, the package came, inside were 2 face clothes. Thank God I paid with a credit card, 4 more weeks, I got my money back from Visa. Not a good deal.


Posted By: Tars Tarkas
Date Posted: 10 Nov 2019 at 7:33pm
Originally posted by crazycoyote

I quit buying directly from China, I don't trust dealing with them. In June I ordered 2 electric folding Trikes at $199.00 each, and waited 4 weeks for delivery, the package came, inside were 2 face clothes. Thank God I paid with a credit card, 4 more weeks, I got my money back from Visa. Not a good deal.

You have to be really careful about batteries from China from what I hear.  They use cheap, off-brand cells, cheap BMSs, and since Lithium batteries are Hazmat, there's no sending them back.

As for those e-trikes, you can't get one decent bike battery for $199!

Caveat emptor.

TT


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2010 176
FJ Cruiser


Posted By: seafans
Date Posted: 10 Nov 2019 at 8:48pm
My concern that on the trailer tongue that bouncing will dislodge the plates in the battery and short out.  Personal experience with batteries.
1.Do not throw battery into water or make it wet
2.Keep the battery away from heat source
3.Do not throw the battery into fire or heat the battery
4.Forbid to hammer to trample the battery
5.Forbid disassembling the battery in anyway


Posted By: offgrid
Date Posted: 11 Nov 2019 at 6:56am
Originally posted by DavMar

My Lord Olddawgsrule for those prices I can buy three lead acid batteries for every one of those. Yes, I know they have more amp hours and discharge rate but my question is does it make economic sense over lead acid or even sealed glass mat batteries? I'm just wondering what is the advantage now of spending 3 times the money for lithium battery? Educate me please!


3x the price but also about 3x or more the cycle life so for boondock use where you cycle the batts a lot you break about even. But that’s not the real reason. The best reason is weight, or, more accurately, energy density. Lead acid gives you about 10 useable watt hours per pound, Li batteries provide about 5-7 times that. If you don’t need that much energy storage and/or weight in not an issue for you then for sure don’t spend the money on Li batteries.

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2015 Rpod 179
2012 Toyota Highlander


Posted By: Olddawgsrule
Date Posted: 11 Nov 2019 at 7:40am
Okay, let's address the concerns.
First, weight is the key item to me. I actually loose 100lbs of battery weight with minimal loss of amp-hours. The battery move move inside, reducing cable length to the charger and panel, also protecting it from excessive temperature. The Lithium can be brought into my home during the winter and used as emergency power bank (no off gassing). Cost for me is $160 more than what I bought my dual 6v's for.

As for buying from China, I've had good experiences buying through Aliexpress and Alibaba. I do recommend that you know what your buying and 'read' all the spec's carefully. I also check through all the forums I belong to and see if anyone has bought the product (or from) before. One of these batteries has been purchased before (The GTK)

As far as buying batteries with cheap parts.. Don't have to go to China for that to happen.. Some of the best Lithuim Ion batteries are made in China. So, yes, there is good and bad being sold there. Know your product and research them.

I mentioned this above, yet I don't intend to mount to the tongue. No reason to. The reason your Pba's are out there is because they're too dangerous to have inside.

Lastly, Yes weight is the largest concern for me. I know what my power usage is (I boondock a lot) and I know what my recovery is so I know I can comfortably move to a 80ah battery. Every battery has a limit to cycles before they break down. How you cycle effects the life of the battery. My old LA solar battery bank was purchased new. 2 year limited warranty, said they would last 5-7yrs (lucky if I get 10yrs) and they lasted 17yrs. Cycling is key to longevity. Same for the Lithium battery. 

I passed this along for anyone researching or looking for a Lifepo4 and wishes to save $$, here's a way.



-------------
2018 RPOD 182g 'Lily'
2017 Tacoma SR5
Life is good!

https://olddawgsrule.wixsite.com/website - Spirit of Adventure WebSite


Posted By: TheBum
Date Posted: 11 Nov 2019 at 10:48am
One thing you need to be aware of, if you aren't already: LiFePO4 batteries have a very flat voltage curve. While that's nice while there's still charge in the battery, you have little to no warning when it runs out of juice and, consequently, accurate predictions of remaining charge from a monitoring perspective are almost impossible.

-------------
Alan
2016 R-Pod 179 "RaptoRPod"
2019 Dodge Durango GT Plus AWD
Three cats


Posted By: Olddawgsrule
Date Posted: 11 Nov 2019 at 2:54pm
Originally posted by TheBum

One thing you need to be aware of, if you aren't already: LiFePO4 batteries have a very flat voltage curve. While that's nice while there's still charge in the battery, you have little to no warning when it runs out of juice and, consequently, accurate predictions of remaining charge from a monitoring perspective are almost impossible.

Okay, I'll bite... It's still a wattage thing..??!!??


-------------
2018 RPOD 182g 'Lily'
2017 Tacoma SR5
Life is good!

https://olddawgsrule.wixsite.com/website - Spirit of Adventure WebSite


Posted By: podwerkz
Date Posted: 11 Nov 2019 at 5:16pm
Originally posted by TheBum

...accurate predictions of remaining charge from a monitoring perspective are almost impossible.

Not impossible. Look at any smartphone or laptop, it shows a pretty accurate indication of charge remaining, and that battery is a lithium battery with a flat voltage discharge curve.

The technology is just different, that's all. You can buy li-compatible coulomb counters or li-compatible amp counters (battery monitors) that will keep track of the energy stored and energy used.


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r・pod 171


Posted By: TheBum
Date Posted: 11 Nov 2019 at 6:33pm
Originally posted by Olddawgsrule


Originally posted by TheBum

One thing you need to be aware of, if you aren't already: LiFePO4 batteries have a very flat voltage curve. While that's nice while there's still charge in the battery, you have little to no warning when it runs out of juice and, consequently, accurate predictions of remaining charge from a monitoring perspective are almost impossible.

Okay, I'll bite... It's still a wattage thing..??!!??


No, it's an energy thing, as in amp-hours.

-------------
Alan
2016 R-Pod 179 "RaptoRPod"
2019 Dodge Durango GT Plus AWD
Three cats


Posted By: GlueGuy
Date Posted: 11 Nov 2019 at 7:11pm
I prefer watt hours. Easier to deal with parallel and/or serial batteries.

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bp
2017 R-Pod 179 Hood River
2015 Ford F150 SuperCrew 4WD 3.5L Ecoboost


Posted By: DavMar
Date Posted: 11 Nov 2019 at 7:12pm
Originally posted by Olddawgsrule

Every battery has a limit to cycles before they break down. How you cycle effects the life of the battery. My old LA solar battery bank was purchased new. 2 year limited warranty, said they would last 5-7yrs (lucky if I get 10yrs) and they lasted 17yrs. Cycling is key to longevity. Same for the Lithium battery.

I passed this along for anyone researching or looking for a Lifepo4 and wishes to save $$, here's a way.


Any tip you can pass on to save money on batteries be them LA or Lithium I'm sure is much appreciated by all on this forum. It also reads to me as you did your homework on manufacture spec's and vendor to buy from in China. Your more then right allot of the Lithium and Glass Mat batteries we buy sadly do come from overseas.

I can more then see the advantage of Lithium batteries if you have the money to spend on them I say I go for it, especially if you do allot of boon-docking. Yet, here is my counter argument to you of Lead Acid verses Lithium. Other then weight savings, no argument there your win hands down. Your said from two lead acid batteries you got 17 years use out of them, which is exceptional. Though even at ten years life span if you divided the cost for Lithium per year and then Lead Acid you tell me which is more economical to use not factoring in the few pound of weight savings? Not to be crass but please do convince me and everyone else here that it makes economical sense to trash our Lead Acid for Lithium batteries.



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Dave & Marlene J with Zoey the
wonder dog.
2017 Rpod 180
2016 Toyota Tacoma SR5 4x4
Lexington, NC


Posted By: crazycoyote
Date Posted: 11 Nov 2019 at 11:07pm
very interesting info, but I'll stick to my 2 Golf Cart 6v batterys, as Costco is the next town down, if I need to replace them.


Posted By: Olddawgsrule
Date Posted: 12 Nov 2019 at 8:21am
Originally posted by DavMar

Yet, here is my counter argument to you of Lead Acid verses Lithium. Other then weight savings, no argument there your win hands down. Your said from two lead acid batteries you got 17 years use out of them, which is exceptional. Though even at ten years life span if you divided the cost for Lithium per year and then Lead Acid you tell me which is more economical to use not factoring in the few pound of weight savings? Not to be crass but please do convince me and everyone else here that it makes economical sense to trash our Lead Acid for Lithium batteries.


Please do understand, I'm a longtime LA battery guy. Yet here comes a breakdown. If you want a battery to last, for years, water regularly and cycle carefully.
A standard LA 12v battery (marine). Let's work with a 575 CCA or roughly 90ah. To cycle for endurance it should only be drawn to 75% of SOC. That puts us at only 22.5amps of usable power. A Duracell will cost you $95. You get 10% off for online purchase, now $85.50. What's that break down to? 
 $3.80 a usable amp. 

It is said, AGM's and Gel's can be drawn deeper, yet I 'read' only another 5-8% or so. Kinda matches out in cost per usable amp when you factor the addiditonal costs of these. Only what I read mind you.. I have no first hand knowledge on these.

Now Lithium, I just bought a 60ah for $225 shipped to my door. Lithium is rated differently as in it's rated to cut-off voltage. This gives me 54ah usable and a cost of 
 $4.16 a usable amp  

All in for my dual 6v's Right around $250 (batts, cables, box and trade-ins). I determine my usable at 105ah. Here's the deal on Batteries!
$2.85 a usable amp (No trade factored $50 added to cost)

It's not 2-3X the cost when you look at as 'usable' ah's.. 

Then there's the Battleborn folks. That's 400% higher per usable amp. Now there's your "I can buy several LA's" for the same cost. 





-------------
2018 RPOD 182g 'Lily'
2017 Tacoma SR5
Life is good!

https://olddawgsrule.wixsite.com/website - Spirit of Adventure WebSite


Posted By: Olddawgsrule
Date Posted: 12 Nov 2019 at 8:37am
Originally posted by TheBum


No, it's an energy thing, as in amp-hours.

Huh?? Care to elaborate a bit?


-------------
2018 RPOD 182g 'Lily'
2017 Tacoma SR5
Life is good!

https://olddawgsrule.wixsite.com/website - Spirit of Adventure WebSite


Posted By: TheBum
Date Posted: 12 Nov 2019 at 2:13pm
Originally posted by Olddawgsrule


Originally posted by TheBum

No, it's an energy thing, as in amp-hours.

Huh?? Care to elaborate a bit?


Power (e.g. wattage) is energy expended per unit time. It's only a rate, not a capacity. The same battery can output 10W or 100W, but the more watts it outputs, the less time it'll take to drain the battery. To look at it another way, a LA battery and a LiFePO4 battery can output the same wattage, but the amount of time it'll take to drain the batteries is dependent on the energy stored in the battery.

LiFePO4 batteries have a higher energy-to-weight ratio than LA batteries do and they can output a large amount of wattage, but they're a bit more finicky on how you charge them, i.e. they're only good for a limited number of charge cycles, so it's a bad idea to trickle charge them: it reduces the service life of the battery because it's essentially cycling continuously.

-------------
Alan
2016 R-Pod 179 "RaptoRPod"
2019 Dodge Durango GT Plus AWD
Three cats


Posted By: GlueGuy
Date Posted: 12 Nov 2019 at 8:00pm
Originally posted by TheBum

 Power (e.g. wattage) is energy expended per unit time. It's only a rate, not a capacity. 
Watts is power. Watt-hours is power over time. If you follow electric vehicles at all, you will see that all the batteries are now rated in KWH (kilowatt-hours).

Interesting side note. The EPA considers 33.5 KWH to be roughly equivalent to 1 gallon of gasoline. That means that an SR+ Tesla Model 3 with a 60 KWH battery has roughly 1-3/4 gallons in the "tank". The amazing thing is that it can go almost 250 miles on that. That is approximately 140 miles per "gallon".


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bp
2017 R-Pod 179 Hood River
2015 Ford F150 SuperCrew 4WD 3.5L Ecoboost


Posted By: DavMar
Date Posted: 12 Nov 2019 at 9:06pm
Hmmm.... according to Olddawgsrule breakdown (and thank you for the details) that it looks to me soon in the near future the cost for Lithium will be comparable to Lead Acid per amp hour. Yes, there is no argument about the Lithium out preforming Lead Acid and believe me when the day comes I can replace my Lead Acid batteries for near the price of Lithium it will be bye bye Lead Acid. Though for seasonal campers that camp were there is electric available or just occasional boon-dockers the cost of upgrading to Lithium just don't make sense to me, yet. I hope in the future as Lithium prices drop that does make sense because I would love nothing more then to be done with Lead Acid batteries.


-------------
Dave & Marlene J with Zoey the
wonder dog.
2017 Rpod 180
2016 Toyota Tacoma SR5 4x4
Lexington, NC


Posted By: offgrid
Date Posted: 13 Nov 2019 at 4:15am
Actually Li batteries are less finicky to charge and maintain than PbA’s. You can leave them at partial state of charge for long periods without damage. You don’t need a complex multistage charger. Just a simple max cutoff voltage is fine. No trickle charging needed. No water adding.

There are a couple of don’ts with Li. Do not overcharge, ever. Do not use them at cold temps. Warm them up first. Don’t discharge them 100% (that applies to PbA’s as well of course).

So they aren’t harder to manage, just different.

As for cost to convert from PbA to Li, the batteries themselves are close enough in cost now that you break even or come out ahead if you boondock and keep your trailer long enough to benefit from the much longer cycle life of the Li batteries. But all your charge control equipment needs to get changed too (a/c charger, tow vehicle charging, and solar). That significantly changes the cost equation.

Re energy vs power, let’s keep our measurement units straight. Amperes are units of electric current. Volts are units of electric potential. Volts x amps = watts which are units of power. Energy is power x time = watt hours. So watts = volts x amps x time.

Batteries are energy storage devices. But they are generally rated in terms of how long they can provide a given amount of current while being discharged. That is amp hours = amps x time. The reason for using amp hours and not watt hours is because the voltage delivered by the battery changes during discharge. So for our purposes it’s easier and more accurate to use amp hours to compare different batteries as long as you are comparing two nominal 12V batteries.





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2015 Rpod 179
2012 Toyota Highlander


Posted By: Olddawgsrule
Date Posted: 13 Nov 2019 at 7:18am
Originally posted by TheBum

Originally posted by Olddawgsrule


Originally posted by TheBum

No, it's an energy thing, as in amp-hours.

Huh?? Care to elaborate a bit?


Power (e.g. wattage) is energy expended per unit time. It's only a rate, not a capacity. The same battery can output 10W or 100W, but the more watts it outputs, the less time it'll take to drain the battery. To look at it another way, a LA battery and a LiFePO4 battery can output the same wattage, but the amount of time it'll take to drain the batteries is dependent on the energy stored in the battery.

LiFePO4 batteries have a higher energy-to-weight ratio than LA batteries do and they can output a large amount of wattage, but they're a bit more finicky on how you charge them, i.e. they're only good for a limited number of charge cycles, so it's a bad idea to trickle charge them: it reduces the service life of the battery because it's essentially cycling continuously.

Well, now I have a clue as to what you were implying. I agree with Glue on this.. Wattage is 'power' and watt hours is power over a period of time. 


-------------
2018 RPOD 182g 'Lily'
2017 Tacoma SR5
Life is good!

https://olddawgsrule.wixsite.com/website - Spirit of Adventure WebSite


Posted By: Olddawgsrule
Date Posted: 13 Nov 2019 at 7:36am
Originally posted by offgrid

Actually Li batteries are less finicky to charge and maintain than PbA’s. You can leave them at partial state of charge for long periods without damage. You don’t need a complex multistage charger. Just a simple max cutoff voltage is fine. No trickle charging needed. No water adding.

There are a couple of don’ts with Li. Do not overcharge, ever. Do not use them at cold temps. Warm them up first. Don’t discharge them 100% (that applies to PbA’s as well of course).

So they aren’t harder to manage, just different.

As for cost to convert from PbA to Li, the batteries themselves are close enough in cost now that you break even or come out ahead if you boondock and keep your trailer long enough to benefit from the much longer cycle life of the Li batteries. But all your charge control equipment needs to get changed too (a/c charger, tow vehicle charging, and solar). That significantly changes the cost equation.

Re energy vs power, let’s keep our measurement units straight. Amperes are units of electric current. Volts are units of electric potential. Volts x amps = watts which are units of power. Energy is power x time = watt hours. So watts = volts x amps x time.

Batteries are energy storage devices. But they are generally rated in terms of how long they can provide a given amount of current while being discharged. That is amp hours = amps x time. The reason for using amp hours and not watt hours is because the voltage delivered by the battery changes during discharge. So for our purposes it’s easier and more accurate to use amp hours to compare different batteries as long as you are comparing two nominal 12V batteries.


Again, thank you and well said. 

I deal in wattage mainly to track what is used and what is replaced. Dis-charge/charge cycle. My meters track this for me as watt-hours. I would be close if I tracked amps, yet as you say, wattage changes according to solar in voltage and battery out voltage. Much prefer tracking with wattage.

Also much easier in a power audit when you have both AC & DC appliances. 


-------------
2018 RPOD 182g 'Lily'
2017 Tacoma SR5
Life is good!

https://olddawgsrule.wixsite.com/website - Spirit of Adventure WebSite


Posted By: GlueGuy
Date Posted: 13 Nov 2019 at 10:10am
Originally posted by offgrid

Re energy vs power, let’s keep our measurement units straight. Amperes are units of electric current. Volts are units of electric potential. Volts x amps = watts which are units of power. Energy is power x time = watt hours. So watts = volts x amps x time.
All the way up to the end you had me. watt-hours (energy) = volts x amps x time.

... and I still prefer using watts. Precisely because amps will vary by voltage. Unless the load is purely resistive, the amps will go up as the voltage goes down. This is particularly noticeable with lead-acid batteries because their voltage changes with their state of charge.


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bp
2017 R-Pod 179 Hood River
2015 Ford F150 SuperCrew 4WD 3.5L Ecoboost


Posted By: offgrid
Date Posted: 13 Nov 2019 at 2:01pm
Originally posted by GlueGuy

 All the way up to the end you had me. watt-hours (energy) = volts x amps x time.

... and I still prefer using watts. Precisely because amps will vary by voltage. Unless the load is purely resistive, the amps will go up as the voltage goes down. This is particularly noticeable with lead-acid batteries because their voltage changes with their state of charge.

Thanks for the correction. Embarrassed

Which loads are constant power (current goes up as voltage goes down)? LED's aren't, water pumps aren't, fans aren't. Those are the main 12V loads in the trailer. 

The reason for working in amp hours is that it makes load calcs, battery sizing, and solar sizing easier, not that you can't do it either way. That's how the off grid solar industry does it and why. If you want to work in watt hours that's fine too, you just have to be careful to apply the correct conversion factors for battery round trip, charger, and solar array efficiencies. No need for a debate about it I don't think. 


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2015 Rpod 179
2012 Toyota Highlander


Posted By: jato
Date Posted: 13 Nov 2019 at 6:49pm
There are a couple of don’ts with Li. Do not overcharge, ever. Do not use them at cold temps. Warm them up first. Don’t discharge them 100% (that applies to PbA’s as well of course).  posted by OFFGRID

Here I sit with my pair of nearly 9 year old 12v Interstate group size 24 deep cycles, considering the Lithium until I read the above post by Offgrid.  So . . . . do not use them at cold temps.  Hmmm, for the majority of the time we have camped with our 177 over the past nearly 9 years the bulk has been in the shoulder months (when it is colder) and where electricity is not available.  So if and when these give up the ghost it looks like I will go back the the LA style, but maybe look at a pair of golf cart batteries instead.  For the most part we change out each battery when it gets to 12.2 volts, hence that may be part of the reason they have lasted as long as they have.  Also regular cleaning on top with baking soda and keeping an eye on the water levels.  

Being in the golf industry for over 40 years I have found it interesting how Yamaha, about 6+ years ago went to the 48 volt system.  No, they do not use 4 12v batteries but 6  8v batteries.  Hopefully there will be enough demand for the 6v ones (like the old 36v electric carts had) so that they don't become discontinued.


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God's pod
'11 model 177
'11 Ford F-150
Jim and Diane by beautiful Torch Lake
"...and you will know the Truth and the Truth will set you free."


Posted By: offgrid
Date Posted: 14 Nov 2019 at 7:09am
Keeping a Li battery warm shouldn't really be a show stopper if you would otherwise want to make the switch from PbA. In an rPod I would suggest placing the Li battery inside the heated part of the trailer somewhere. Since they don't outgas or need easy access for adding water that would be fine and the battery wouldn't be subject to extreme temperatures that way. 

That being said if there is no other compelling reason to make the change (reducing weight and or increasing capacity) then sticking with PbA and all your existing charging gear makes economic sense. The 6V configuration is common in the RV and off grid solar world too so I think there's not much worry it will get discontinued anytime soon. 


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2015 Rpod 179
2012 Toyota Highlander


Posted By: Olddawgsrule
Date Posted: 14 Nov 2019 at 8:14am
Originally posted by jato

There are a couple of don’ts with Li. Do not overcharge, ever. Do not use them at cold temps. Warm them up first. Don’t discharge them 100% (that applies to PbA’s as well of course).  posted by OFFGRID


Well, you don't wish to over-charge a Pba either.. that's called boiling the battery. 

Li is more sensitive to cold where Pba is to heat. Both batteries types survive best at room temp, 68F or 20C. It is stated that every 8C or 46F increase you cut the life of the Pba in half (I assume same is true with decrease).
Lithium now has the advantage in warm weather climates.
It is also stated that a Pba will loose capacity in colder weather. Stated that at 32F or 0C you've lost 15% of your battery capacity. If your camping at 0F or 18C you've lost almost a 3rd of your battery capacity

Neither really likes cold weather.

The additional benefit to Li is it 'can' come into the living space and operate normally with no hazard. Again, it can come into the house and operate there as a UPS or Backup power.

Going Li is a choice to be made by ourselves and our own intentions. What works for me, may not for you. My hesitance was multiple: Cost being #1, verifying my power audit as to how we camp & what we actually use and finally weight. 
For me, it now makes sense. 


-------------
2018 RPOD 182g 'Lily'
2017 Tacoma SR5
Life is good!

https://olddawgsrule.wixsite.com/website - Spirit of Adventure WebSite


Posted By: offgrid
Date Posted: 14 Nov 2019 at 9:16am
Originally posted by Olddawgsrule


Well, you don't wish to over-charge a Pba either.. that's called boiling the battery. It won't really hurt anything if you overcharge a flooded PbA battery as long as you keep the plates covered with distilled water. OTOH, a Li battery could catch fire under the same conditions. A so-called "sealed" (actually valve regulated) PbA battery will also severely overheat under overcharge conditions, ask me how I know.Shocked

Li is more sensitive to cold where Pba is to heat. Both batteries types survive best at room temp, 68F or 20C. It is stated that every 8C or 46F increase you cut the life of the Pba in half (I assume same is true with decrease). There are two determining factors in battery life (both PbA, Li, and others), shelf life aka corrosion life and cycle life. Shelf life determines how long a battery can sit on a shelf not being cycled, and is very dependent on storage temperature, both below (longer life) and above (shorter life) normal room temp. Cycle life determines how many cycles to a given depth of discharge a battery can handle. The battery will reach its end of life, typically stated as having 80% of its original capacity, when the first of these two factors occurs. 
Lithium now has the advantage in warm weather climates. Not really. A Li battery's life is also determined by temperature, just ask folks in Phoenix who bought a first gen Nissan leaf EV. All the EV mfgs (I think) use active liquid battery cooling for this reason, except Nissan who is still doing air cooling for some reason. We don't need to do that with our batteries because the charge and discharge rates are much lower than in an EV. 
It is also stated that a Pba will loose capacity in colder weather. Stated that at 32F or 0C you've lost 15% of your battery capacity. If your camping at 0F or 18C you've lost almost a 3rd of your battery capacity The capacity is actually still there, you just can't get it out because the internal resistance of the battery is higher at low temps due to the slowed chemical reaction rates. If you warm up that battery the capacity will "magically" reappear. 

Neither really likes cold weather. But there is a big difference. If you try to recharge a Li battery at low temps it will undergo permanent damage because the chemical reaction occurring at the battery anodes changes. With PbA batteries everything is just slowed down, no long term harm done unless you leave them really discharged and allow the electrolyte to freeze. So, be sure you warm up your Li battery before trying to recharge it. 

The additional benefit to Li is it 'can' come into the living space and operate normally with no hazard. Again, it can come into the house and operate there as a UPS or Backup power. Yep, agreed. 

Going Li is a choice to be made by ourselves and our own intentions. What works for me, may not for you. My hesitance was multiple: Cost being #1, verifying my power audit as to how we camp & what we actually use and finally weight. 
For me, it now makes sense. For me too, I want to be able to run a/c off grid and need about 4kWh minimum useable capacity to do so. That would weigh in at about 400 lbs with PbA but only about 60 lbs with Li. 


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2015 Rpod 179
2012 Toyota Highlander



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