jaycocreek
Idaho
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Joined: 12/28/2013
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Solar Engineering posted a pretty good video on a $300 ish lifepo4 teardown..Pretty profesional IMHO and somewhat different/more detail than Will Prowses tear downs...
Lot's of people have asked what kind of lithium battery you get for the ridiculous low prices we are seeing..This person notes a DIY would cost about the same as this grade A cased battery..And he is giving it away...
$320 lifepo4 tear down by solar engineering..
Lance 9.6
400 watts solar mounted/200 watts portable
500ah Lifep04
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Tom_M
New Hope, MN
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Joined: 04/24/2011
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The battery tested turned out that it had no low temperature cut-off. Will Prowse has done similar tests with the same results for the cheap batteries. If you plan on using the battery and know it will not get down below freezing it would be a good choice.
Tom
2005 Born Free 24RB
170ah Renogy LiFePo4 drop-in battery 400 watts solar
Towing 2016 Mini Cooper convertible on tow dolly
Minneapolis, MN
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PerryB67
Lanesboro, Minnesota
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Joined: 07/07/2017
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Tom_M wrote:The battery tested turned out that it had no low temperature cut-off. Will Prowse has done similar tests with the same results for the cheap batteries. If you plan on using the battery and know it will not get down below freezing it would be a good choice. No Thanks!
Another Minnesota resident that finds a low-temp shutoff mandatory.
Enjoy,
Perry
2016 Bigfoot 25RQ
2019 F150 Max Tow, Max Springs, 3.5 EB Quad Cab
Victron 712, Victron 100/20, Victron 100/30
160 Watts on the Roof, 100 watt portable
Two 100 ah SOK LFP Batteries
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3 tons
NV.
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Joined: 03/13/2009
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PerryB67 wrote:Tom_M wrote:The battery tested turned out that it had no low temperature cut-off. Will Prowse has done similar tests with the same results for the cheap batteries. If you plan on using the battery and know it will not get down below freezing it would be a good choice. No Thanks!
Another Minnesota resident that finds a low-temp shutoff mandatory.
Enjoy,
Perry
From my ‘actual’ 200a/h LFP off-grid experiences, Low temp shutoff might matter most where one lacks the option for either interior mounting, or the ability to manually shut-off their charging sources (e.g. solar controller) - it doesn’t mean that you can’t continue to camp and discharge the battery…For the uninitiated, where ‘attended charging’ is one’s practice, low temp shutoff is not necessarily of high value - JMO
Consider, that with the vast increase in ‘usable capacity’ (often double…), in my camping scenarios (often, deferred charging) there’s always been enough remaining reserve to get thru to and exploit the next available harvest window, and since LFP’s recovery rate is much faster than sluggish lead-acid, and their voltage curve is uber flat, then, except for an occasional cell-rebalancing there’s seldom a real need for a full recharge…In fact, even in the snow my FLA target charge range is somewhere between *30-90% SOC - This, in my own view is what paradoxically seems to elude many FLA veterans…I was even able to run the microwave at over 130 dc amps when below 05% SOC, followed-up by making coffee (125a!) using the Keurig!!
*30%, this a nearly a 60 usable a/hr remaining reserve, using about 20 a/hrs (mostly furnace) throughout the night…
Storing LFP is even easier since their self-discharge rate is uber low, thus (assuming, disconnected) they can be stored in freezing weather…
3 tons
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Lwiddis
Southern California :(
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Joined: 08/12/2016
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Interesting observations 3 tons. My 200 AH Lithium is new to me. So far very satisfactory.
Winnebago 2101DS TT & 2022 Chevy Silverado 1500 LTZ Z71, WindyNation 300 watt solar-Lossigy 200 AH Lithium battery. Prefer boondocking, USFS, COE, BLM, NPS, TVA, state camps. Bicyclist. 14 yr. Army -11B40 then 11A - (MOS 1542 & 1560) IOBC & IOAC grad
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3 tons
NV.
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Lwiddis wrote:Interesting observations 3 tons. My 200 AH Lithium is new to me. So far very satisfactory.
Yep, the mythologies surrounding LFP’s seems to run a bit quixotic - lol…I’d again posted simply in an attempt ‘to inform’…
FWIW, for purposes of a sheer ‘wild-arse test’ only, I was also able to briefly run the microwave at even zero % SOC - this with not even a low voltage alarm on the inverter!!…My single 200 a/hr LFP load-tested out at an actual 215 a/hrs using a 500w halogen work lamp…
The uninitiated will likely have some (extreme??) difficulty wrapping their minds around this, yet they’d never seriously consider purchasing a non-Lithium portable power tool - lol
Then there’s the abundance of ‘charging myths’ (hoops??) which some suggest to be nearly insurmountable… This claim too is silly…With a standard PD, simply add a Charge Wizard (for 14.4v boost mode) and discontinue charging whenever it makes sense to you, mostly depending on one’s expected power usage - no need to routinely achieve 100% SOC…
3 tons
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n0arp
FT
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Joined: 08/20/2016
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In our fifth wheel, our bank lives in a sectioned off portion of our passthrough bay, with a small furnace vent tapped into it. Additionally, we have a 200W electric heater that is powered by a thermostatic outlet that turns on at 35F, and off at 45F. This ends up using very little energy - especially since our furnace is usually on low in cold temps. Victron's DVCC now allows you to set a a minimum charge temp, which we utilize as a failsafe.
For the truck camper, the bank sits in an interior cabinet, that is as temperature controlled as the rest of the living area. We monitor temps in there, but even in single digit outside temps have never seen it below around 50F. We could always add a heater like mentioned above, if necessary. The batteries themselves are always a few degrees warmer than ambient since they're actively being discharged (or charged, for that matter).
Having a low temp cutoff is critical if they're sitting on the tongue of your trailer, but otherwise, easy enough to work around. Low temp charging is mentioned often in argument against LiFePO4 on these forums, but I've long dismissed it as people trying to justify why they haven't upgraded or that their lead acid banks are somehow better. More or less the same way I see most posts in gas vs diesel threads.
* This post was
edited 01/11/22 01:53pm by n0arp *
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3 tons
NV.
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Yep, Lots to do about mostly nothing, but as we’ve all learned about the vagaries of human nature, ‘FEAR sells’ - far too many pages of errant uninformed speculations will readily attest to that - lol
3 tons
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Itinerant1
Itinerant
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Joined: 05/23/2017
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3 tons wrote:Yep, Lots to do about mostly nothing, but as we’ve all learned about the vagaries of human nature, ‘FEAR sells’ - far too many pages of errant uninformed speculations will readily attest to that - lol
3 tons
With almost 6 years of everyday use and over 1,800 partial cycles of 35-45%+ DOD at various SOC. I do find amusement in what some post about lfp. It seems the new thing now that pops up more is longevity instead of use staying within the parameters of the batteries.
12v 500ah, 20 cells_ 4s5p (GBS LFMP battery system). 8 CTI 160 watt panels (1,280 watts)2s4p,Panels mounted flat. Magnum PT100 SCC, Magnum 3012 hybrid inverter, ME-ARC 50. Installed 4/2016 been on 24/7/365, daily 35-45% DOD 2,237+ partial cycles.
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3 tons
NV.
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Itinerant1 wrote:3 tons wrote:Yep, Lots to do about mostly nothing, but as we’ve all learned about the vagaries of human nature, ‘FEAR sells’ - far too many pages of errant uninformed speculations will readily attest to that - lol
3 tons
With almost 6 years of everyday use and over 1,800 partial cycles of 35-45%+ DOD at various SOC. I do find amusement in what some post about lfp. It seems the new thing now that pops up more is longevity instead of use staying within the parameters of the batteries.
Well, LFP’s are extremely robust…One may choose to incessantly fiddle around to be certain to ‘dial in’ their purported 5,000 cycles, or maybe just enjoy life, overcome the impulse to micromanage and be perfectly content to settle for a mere 4,000 - pick your poison - lol!
Yet, I believe simply by not overcharging (or unnecessarily leaving for extended periods on a charger), and doing an occasional cell re-balancing, it shouldn’t be all too difficult to optimize the batts upper limit longevity - JMO
3 tons
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