Is there advantage between running a 2-100ahr to 1-200ahr

[elhora]

Originally Posted by wantabe351

I've decided to go with Lithium batteries for my RV, and shopping for batteries I'm thinking of starting with a 200ahr battery now and wondered is there a advantage to using 2 -100ahr battery to 1-200ahr battery...

If you are going to start with 200ahr battery and expend $800 and in the future expand the system, I will expend a couple of hundred dollars more and put a 300ahr battery, now the real question is, how are you going to charge it?

[Pianotuna]

If you want high discharge rates, consider SiO2. A 100 amp-hour can do 9 C for 5 seconds and can do 4 C continuous.

[fstruys]

For most of us considering switching to LiFePo4 batteries, I don't believe that a high discharge rate is very important, although my three LifeBlue LB12300HCLT batteries can provide 600 amps for 30 minutes. For those of us that do a lot of dry camping, a low battery discharge rate over a longer period is much more appealing, especially considering their fairly consistent output voltage.


I find it extremely interesting to read all of the arguments against switching to LiFePO4 type batteries. Certainly, the initial up-front costs are intimidating, but averaging their performance over their warranted lifetime DOES compare favorably to lead acid batteries.


I guess it would be like to trying to maintain the opinion that horse-powered transportation is better than any engine-powered transportation. In fact, after having driven an all-electric car during the past 5 1/2 years, I cannot imagine EVER going back to an ICE-powered car!


Felix & Becky
Vancouver, WA
2007 37' Country Coach Allure, 1700 watts solar, 900 AH LiFePo4,
400 watt Air-X

[Phil G.]

Originally Posted by fstruys

For most of us considering switching to LiFePo4 batteries, I don't believe that a high discharge rate is very important, although my three LifeBlue LB12300HCLT batteries can provide 600 amps for 30 minutes. For those of us that do a lot of dry camping, a low battery discharge rate over a longer period is much more appealing, especially considering their fairly consistent output voltage.

I find it extremely interesting to read all of the arguments against switching to LiFePO4 type batteries. Certainly, the initial up-front costs are intimidating, but averaging their performance over their warranted lifetime DOES compare favorably to lead acid batteries.

I guess it would be like to trying to maintain the opinion that horse-powered transportation is better than any engine-powered transportation. In fact, after having driven an all-electric car during the past 5 1/2 years, I cannot imagine EVER going back to an ICE-powered car!

Felix & Becky
Vancouver, WA
2007 37' Country Coach Allure, 1700 watts solar, 900 AH LiFePo4,
400 watt Air-X

I would consider switching the two 115 AH 12V Group 31 deep cycle AGM batteries in our RV to a couple of equivalent physical sized and AH rated LiFePo4 batteries if I could just drop them in place of the AGM batteries.

However, also changing out the RV's stock fixed voltage converter/charger to deal with LiFePo4 batteries is something I just don't care to mess with (... even though I'm an EE by education and career). My stock 13.6-13-8V fixed voltage converter/charger is still functioning fine after many years use and it - along with the engine alternator - takes care of the AGM batteries nicely on RV camping trips.

Also on another level - I won't feel comfortable with lithium-based batteries and EVs everywhere until "the world" comes up with a macro level sustainable way of dealing with lithium mineral production, lithium battery disposal, and clean enough electricity generation and safe distribution so as to deal with a world full of EVs. At that point, if I'm still alive enough to drive, I'll gladly consider getting rid of my 1995, 2002, and 2005 ICE-powered vehicles.

[fstruys]

Many packaging configurations of LtFePo4 batteries are currently available; in my case, I replaced the original-equipment-size 8D-sized batteries with 8D size lithium batteries, weighing almost half what the Lifeline AGM 8ds I had been using. These Lifeline include a Bluetooth-accessible BMS & internal heaters allowing charging down to -4 degrees F. This is a PERFECT, drop-in replacement for my RV increasing my useable AH from 500 to 900, going from four 8Ds to three 8Ds which allowed me enough extra space to install a second, 3000 watt Xantrex RS3000 charger/inverter. This addition doubled both my inverter output capacity AND charging capacity. An additional benefit of doubling my charging amperage to 300 amps is the 50% reduction in generator run time to fully recharge my lithium batteries.


As far as concerns about lithium production, disposal or recycling, like everything else, it seems, I'd believe this to be the lesser to 2 evils when considering the burning of fossil fuels, greenhouses gasses, pollution, etc., by ICEs.


Felix & Becky
2007 CC Allure, 1700 watts solar, 900 AH LiFePo4, 400 watt Air-X

[LargeMarge]

Toss-up.
.
* A 200 is engineered to be a 200, two 100s may be compatible on a good day.
* A 200 operates just fine without cables between its internals, two 100s *generally* require cables to complete the circuit.
.
One 200 might go on the fritz, stranding you.
One 100 in a pair of 100s can still plug along.
.
.
An alternative:
Build your bank using two or five or twenty-four 200s.

[Camper25]

I use two 100ah.... I don't want to be stranded with just one bad battery.

[Phil G.]

In my opinion two 12V Group 31 size LiFePO4 wired in parallel is the way to go because of the battery power redundancy one gets if one of the pair should ever fail when drycamping. Don't forget that not only can the individual cells within the battery itself fail, but the BMS system can also fail due to the combined failure rates of the many electronic components contained within the circuitry of the BMS.

Given the above and if dollars spent for amp hours is no object - but minimizing battery space is also a high priority - I'd go with a couple of these 12V Group 31 size LiFePO4 batteries for maximum capacity per cubic inch of storage space:
https://www.lithiumion-batteries.com...on-battery.php

[Souljourner]

I’ve been avidly reading this thread because I’m looking to replace my current batteries with lithium and would like to do so this week. I hope I’m not commandeering this thread by posting my question here, but I wanted to take advantage of all the knowledgable folks who have been posting and my question is related. Happy to repost as a new thread if that’s proper etiquette. :-)

Regarding the amp hour question of this thread - how do I know how much I should buy? I have about 30 boondocking trips under my belt so I have a good idea of my current usage. I have a 22’ TT, don’t care about AC or microwaves, (did fine with my rechargeable fans at high 90’s temps this summer), my only elec usage is basically a few LED lights for an hour or two and recharging my phones overnight and the water pump, which I only turn in when using, as well as parasitic draw. My 190 watt solar panels have given me more than enough power to keep my current batteries charged.

I believe I know the features I’m looking for in a lithium battery. Just not sure of size?

Any guidance would be greatly appreciated. I’d rather spend my money on a better battery than buying a bigger battery than I need.

[Newps]

Originally Posted by Souljourner

the water pump, which I only turn in when using,

?? Doesn't your water pump turn off after you shut the faucet off?

[Itinerant1]

Originally Posted by Souljourner

I’ve been avidly reading this thread because I’m looking to replace my current batteries with lithium and would like to do so this week. I hope I’m not commandeering this thread by posting my question here, but I wanted to take advantage of all the knowledgable folks who have been posting and my question is related. Happy to repost as a new thread if that’s proper etiquette. :-)

Regarding the amp hour question of this thread - how do I know how much I should buy? I have about 30 boondocking trips under my belt so I have a good idea of my current usage. I have a 22’ TT, don’t care about AC or microwaves, (did fine with my rechargeable fans at high 90’s temps this summer), my only elec usage is basically a few LED lights for an hour or two and recharging my phones overnight and the water pump, which I only turn in when using, as well as parasitic draw. My 190 watt solar panels have given me more than enough power to keep my current batteries charged.

I believe I know the features I’m looking for in a lithium battery. Just not sure of size?

Any guidance would be greatly appreciated. I’d rather spend my money on a better battery than buying a bigger battery than I need.

If you're not going to want more luxury than what you're using now just replace with lfp that's equal to what is installed now. If you're willing to spend a little more for possible future power wants double the size of what you have. What you're using now is very minimal and a 100ah will easily take care of it.

[Souljourner]

Originally Posted by Newps

?? Doesn't your water pump turn off after you shut the faucet off?

In an attempt to conserve electricity (I think?) I only turn on the switch for the pump when I need to run water. Is this not accurate?

[Newps]

Originally Posted by Souljourner

In an attempt to conserve electricity (I think?) I only turn on the switch for the pump when I need to run water. Is this not accurate?

Not accurate, the pump doesn't use electricity when it's not actually running.

[Collyn]

The main benefit of using more but smaller batteries is that they are so much easier to move!

Collyn