Master thread for disasters and generators.

BVH

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Ran on the Ultra for 11 hours today and used 45% of capacity going about our normal activities. Theoretically, we could run another 8 hours tomorrow and be left with 10% capacity. This does not count the 11 KWhs stored in the two Pecron systems that can feed the Ultra. We started at 90%, not 100% as mfg recommends charging to 90% and discharging down to 10% to be kind to the batteries. I may change that because we will never get anywhere near 3,500 charge/discharge cycles so I feel we can take a bit more from the pack each cycle. The inverter kicked off after about 5 minutes twice when first turned on. There were some codes but I forgot what they were. (Senior moment) The inverter has a minimum temperature that it will run at. It has a built-in battery heating system for such occasions. I am thinking it kicked off on low temp. Although it was only down to 54F. Once I started it the third time, it ran flawlessly the rest of the day. I think the two, 5 minute runs warmed things up a bit. I used my two Pecron 200 Watt folding solar panels at the same time today. I wired them in Series and fed the Low Voltage solar input. I averaged a rate of about 175 Watts over the 6 hour period. The sky was considerably cloudy most of the time so I would expect to do better on a clear day. I peaked at 325 Watts for some significant periods. That's very good for two, 200 Watt rated panels. It's really fun to look at the units discharge Watts and then look over at the solar input watts and know that I'm reducing the load on the batteries giving me more run time. Coincidentally, we had a 30 minute power outage during my run today and we didn't even know until two neighbors called us to verify that power was out. I told them "I don't know if the power went but we have oodles and oodles of power and are living just fine!" I really, Really, REALLY like the Ultra! Man, if I could just get one more battery!....well, maybe just two more batteries.....Does this never end??? I can add up to two more!! Maybe next month. But it's really difficult to hide the gigantic box from my wife.
 
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Poppy

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I want to replace my 12v 6ah lead acid battery YTX7L-BS that is used to start my harbor freight 3500 generator, with a LiFePO4 battery. The LiFePO4 batteries often come with the warning:
Attention – make sure to only use a compatible lithium charger for this battery

My generator, and my lawnmower will each charge the battery while the engine is running. Is it safe to swap? Is the warning only for an external charger?
 

orbital

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+

It's not an issue of safety Poppy, it's if your generator charging system will even recharge it while running.
I have a LFP powersports battery in a motorbike, it doesn't recharge the battery the way it should (could be a bike issue)?
...meaning it's like putting a 4S battery on a charger set for 3S,, it just doesn't recognize it.
Works, but just have to manually recharge it,, kinda a hassle.

add: remember, you can't recharge a LFP battery below freezing ~ just another factor to consider.
 
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raggie33

*the raggedier*
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my dang terminal broke off my battery its a marine lead acid battery under warrentty but i lost recipt
 

orbital

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Another thing Poppy, and this is most important.

AGM and any lithium battery WILL NOT charge correctly with a standard lead acid 12V charger, WILL NOT!
Both of those chemistries charge at a higher voltage and you need a charger specifically meeting those higher voltage needs.

===== you may be having a charger issue,, not a battery issue =====
Most small powersports batteries are now AGM, standard 12V charger will not charge it properly.

Lastly, never keep a battery connected to a charger unless its a old school lead acid

last year I picked up one of these:


or this is cheaper:

 
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orbital

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Yeah, I guess I could have written my question more clearly.
Will a LIFEPO4 battery charge correctly without the use of an external charger?
+

Likely not, nor the AGM battery you have that's causing you problems.

Need a specific AGM charger like I mentioned above ^ your generator battery could be fine

*** again, never leave a charger on a battery unless it's lead acid
 

raggie33

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can you use multiple chargers to charge one battery lead acid type? or will they just trick each others that the battery is full?
 

KITROBASKIN

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Poppy, sorry that I have forgotten what needs to be done to achieve your objective of going with LFP. Asking Google may get an answer. I would see what voltage your generator is charging. Compare that number with what the LFP battery you wish to get, needs.
 

orbital

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Poppy, hope I didn't confuse you.
Your generator very likely has a AGM battery in it,, nearly all powersports size batteries are now AGM.
The system on your generator to recharge it may not provide enough voltage to charge an AGM or LFP.

You may think you have a battery problem, it very well could be a system recharging problem not having enough voltage.

LFP and AGM recharge at just under 15V, less than that and they won't recharge.

Just mentally figure you need a AGM/LFP charger.


** I have more questions, but I don't want to overload you.
 

three_jeeps

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Yeah, I guess I could have written my question more clearly.
Will a LIFEPO4 battery charge correctly without the use of an external charger?
To answer this question correctly requires that you contact the battery mfg and get a data sheet that describes minimum, ideal, and rapid charging profiles. You need a charger that can charge according to the mfg specs. You may be able to do a simple constant V and I charge but IIRC for LIFEPO4 batteries it stresses them and decreases lifetime of the battery (I need to double check this in my texts). One may also need to monitor battery temp and adjust charge rate accordingly.
Back in the day, I built a programmable, multi battery life testing lab were we could test just about any battery chemistry for charging profiles, efficiency, charge/discharge cycles, varying discharge loads, etc. We had batteries that we ran lifetime tests over 4-5 years. We gathered data mfg never had....any proved some claims as invalid....
 

Poppy

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@orbital thanks for the info. I have a sealed lead acid battery, not a AGM. I charged it with a smart charger, and it takes a charge but doesn't hold it. It is a battery issue.

@KITROBASKIN thanks for the thought. I often find that I forget details of things I once knew. If I hadn't joggled those gray cells in a while the details get lost. LOL, every once in a while they pop up, and I wonder... "Where in the heck did that come from?"

@three_jeeps
contact the battery mfg and get a data sheet that describes minimum, ideal, and rapid charging profiles. You need a charger that can charge according to the mfg specs.
of course they don't list this info in their sales literature, so it would require contacting them as you suggest. I wanted to avoid the hassle. It would be easier to just buy a new lead acid battery for 1/2 to 1/3rd the price, and replace it every three years.

It appears that some LiFePO4 batteries have a built in BMS, and they state that they are the correct size so that they can be a direct swap-in. They also mention that one needs a Li charger for them. Poorly written descriptions, with a lack of information are frustrating, and a waste of time.

I don't want to purchase a LiFePO4 battery only to find that it won't be maintained by the generator while it is running, thusly requiring me to periodically me to put it on charge with an external charger.
 

scout24

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If you completely disconnect the battery once the generator is running, and attach multimeter leads to the positive and negative cables coming from the generator, you'll know how much if any voltage is being sent to the battery to charge it. Probably good to know either way.
 

orbital

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If there is a amp draw from your generator (very possible) an in-line disconnect to one of your wires pos. or neg.
would save you alot of hassle when you go to start your gen and nothing.

or

a quick disconnect to one of your battery terminals


= for just a few seconds reconnecting to use,, you will always have a charged battery when you most need no hassles
 

Poppy

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If you completely disconnect the battery once the generator is running, and attach multimeter leads to the positive and negative cables coming from the generator, you'll know how much if any voltage is being sent to the battery to charge it. Probably good to know either way.
Yes scout, I agree that would be a good thing to know, if just for sh and giggles. I have the battery out sitting in my bedroom, staying nice an warm, but it is dropping voltage anyway. I am going to have to replace it.

@orbital if the generator has an amp draw, there is a short. Possibly a bad diode. IMO it would be better to track it down and FIX it than to put a quick disconnect in.
 

orbital

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Some things can draw a little power, a flashlight with electronic switch, an inverter, a light that connects to a powertool battery.
Doesn't necessarily mean there's a short, especially if there's electronics involved..

The size battery you have is in the *powerpsorts* category. If you can get a true lead acid in that size, get it.... they are very hard to track down.


*atv, generators, motorcycles, lawn mower,,
Yesterday I wanted to start my 3500 watt harbor freight predator inverter generator for its periodic checkup. The battery was dead, again! Last year it was dead, and I pulled it and put it on charge, and kept it indoors all winter.

Fortunately it has a pull start, and she started right up.

I wonder... do these units typically have a parasitic drain?
The unit is only two years old. I am thinking that the battery should be about the same age.
believe that post is from '22 ^^^^^^
 

three_jeeps

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@orbital thanks for the info. I have a sealed lead acid battery, not a AGM. I charged it with a smart charger, and it takes a charge but doesn't hold it. It is a battery issue.

@KITROBASKIN thanks for the thought. I often find that I forget details of things I once knew. If I hadn't joggled those gray cells in a while the details get lost. LOL, every once in a while they pop up, and I wonder... "Where in the heck did that come from?"

@three_jeeps

of course they don't list this info in their sales literature, so it would require contacting them as you suggest. I wanted to avoid the hassle. It would be easier to just buy a new lead acid battery for 1/2 to 1/3rd the price, and replace it every three years.

It appears that some LiFePO4 batteries have a built in BMS, and they state that they are the correct size so that they can be a direct swap-in. They also mention that one needs a Li charger for them. Poorly written descriptions, with a lack of information are frustrating, and a waste of time.

I don't want to purchase a LiFePO4 battery only to find that it won't be maintained by the generator while it is running, thusly requiring me to periodically me to put it on charge with an external charger.

I don't understand 'I want to avoid the hassle'?!?!?!? The only way to know for sure is to understand what type of battery technology you are dealing with is to get the engineering data. Most (e.g 99%) of the time this data is not on a sales sheet - why would it be? It isn't that big of a hassle, It should be somewhere on their website or a short email to the tech support should provide the info (unless you are dealing with a china based product/company then chances of getting anything useful is small so you will have to rely on generic information). Or one can make some guesses and try things but that seems senseless and inaccurate to me, and could result in a shortened battery life, or worse, a safety risk.
 

raggie33

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i got a inverter rated at 2000 watts it only does like 1000 watts is it the batterys? i have to big deep cycle batterys i think 220 amp hours combined do i need to add another?
 
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