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Sealed Lead Acid VS lifepo4 battery

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#1 aalmanni

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Posted 07 March 2021 - 01:09 AM

Hi,

 

Recently I purchased the older Celestron powertank model 18774 as I needed the 3v, 6v, 9v and the 12v output to run a the motors for SkyView pro and electric focuser as well as other regular 12v mount,

 

The question is it worth it to buy the newer LiFePo4 battery rather then the regular SLA /AGM battery.

 

Given the fact that the newer one is 5 times more pricey than the regular one $175 vs $35 canadian

 

By the way, I am waiting for the Celestron Powertank Lithium LT to arrive which will be the main one.

In the future i might want to run a few heater, a dslr camera and or other accessories

 

Thanks in advance

 

 



#2 james7ca

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Posted 07 March 2021 - 01:49 AM

The only "cheap" Lithium power source that I know about is one of the 20Ah Miady Deep Cycle LiFePO4 batteries that are sometimes available on Amazon. I purchased one of these a few weeks ago for just $66 (U.S.) and added a few quick disconnects and a battery box which made the total about $90. It seems every bit as good as one of my 35Ah AGM batteries and weights only about 1/3 as much. Plus, when I purchased my deep-cycle AGM batteries a few years ago they cost $100 each.

 

But, the above only gives me a 12VDC source and so you'll need to spend some additional money to provide regulated outputs at other voltages (which I already had). Also, you may want to get a good Lithium Ion charger to go with the above.

 

I guess what I'm saying is that with your power requirements (3v, 6v, 9v, 12v) you're going to have to pay significantly more for any solution. Plus, the question about AGM versus LiFePO4 is usually one of weight, so if weight is an issue then consider going for LiFePO4. As a general rule of thumb, you'll probably get about twice the runtime out of a LiFePO4 as you would for a similar Ah-rated AGM battery. But, you need to be careful about how a LiFePO4 is rated, since they sometime state a capacity for a lower voltage output (i.e. not 12V).

 

Frankly, unless weight is a significant concern I couldn't see spending five times more for a LiFePO4, unless the LiFePO4 had far greater capacity. 


Edited by james7ca, 07 March 2021 - 01:50 AM.


#3 ngc7319_20

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Posted 07 March 2021 - 02:43 AM

Every time I run the numbers on this, I decide to stick with Sealed Lead Acid.  Weight is not a huge factor in this size.  And then the 5x price difference kinda ends the case for LiFePo4.  

 

If you treat SLA well, and always keep the output voltage above 11V, you can probably get 4 - 6 years from it.   LiFePo4 would need to last say 20 to 30 years to make up the price difference -- no idea if it would go that long.



#4 Supernova74

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Posted 07 March 2021 - 05:40 AM

Admittedly the initial outlay of lifepo4 lithium iron phosphate power bank,tanks,is more financiall in the more long term scenario I think it’s the way to go.as us amateurs don,t mind spending Astronomical amounts of money on the telescope,mount and accessories that we all own, just me personally wouldn’t skimp on the power pack solution either if that’s an option you can choose.yes the lead acid equivalents are a cheaper alternative and are very budget friendly however the draw back is thay don,t like battery drain and don,t hold there charge as well as there LIFo4 counterparts and don,t really have to be recharged if left unattended for 6 mths either depending on the quality of the cell chemistry,I own a tracer uk based high end lifepo4 16ah power bank running my scope and heated dew strap when needed it’s about 75% smaller than celestrons,skywatcher alternative 17ah acid battery power pack. Small, compact easier cable management  and tied via Velcro straps to the side of my fork mount,it also has a shelf life of over 1400+ recharge cycles with a manufactures warranty of 5 years.however if you cannot afford the lifepo4 chemistry stick with acid cell alternative it will serve you well not for years and years on end.


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#5 aalmanni

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Posted 07 March 2021 - 07:12 PM

The only "cheap" Lithium power source that I know about is one of the 20Ah Miady Deep Cycle LiFePO4 batteries that are sometimes available on Amazon. I purchased one of these a few weeks ago for just $66 (U.S.) and added a few quick disconnects and a battery box which made the total about $90. It seems every bit as good as one of my 35Ah AGM batteries and weights only about 1/3 as much. Plus, when I purchased my deep-cycle AGM batteries a few years ago they cost $100 each.

 

But, the above only gives me a 12VDC source and so you'll need to spend some additional money to provide regulated outputs at other voltages (which I already had). Also, you may want to get a good Lithium Ion charger to go with the above.

 

I guess what I'm saying is that with your power requirements (3v, 6v, 9v, 12v) you're going to have to pay significantly more for any solution. Plus, the question about AGM versus LiFePO4 is usually one of weight, so if weight is an issue then consider going for LiFePO4. As a general rule of thumb, you'll probably get about twice the runtime out of a LiFePO4 as you would for a similar Ah-rated AGM battery. But, you need to be careful about how a LiFePO4 is rated, since they sometime state a capacity for a lower voltage output (i.e. not 12V).

 

Frankly, unless weight is a significant concern I couldn't see spending five times more for a LiFePO4, unless the LiFePO4 had far greater capacity. 

Thanks for the clarification, mine in fact has the 3, 6 and 9 v built in with the standard 5.5/2.1mm output and 2 12v output as the picture attached

 

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#6 aalmanni

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Posted 07 March 2021 - 07:13 PM

Every time I run the numbers on this, I decide to stick with Sealed Lead Acid.  Weight is not a huge factor in this size.  And then the 5x price difference kinda ends the case for LiFePo4.  

 

If you treat SLA well, and always keep the output voltage above 11V, you can probably get 4 - 6 years from it.   LiFePo4 would need to last say 20 to 30 years to make up the price difference -- no idea if it would go that long.

Thanks a lot for the suggestion, I can maintain the battery fully charged all the time,



#7 aalmanni

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Posted 07 March 2021 - 07:16 PM

Admittedly the initial outlay of lifepo4 lithium iron phosphate power bank,tanks,is more financiall in the more long term scenario I think it’s the way to go.as us amateurs don,t mind spending Astronomical amounts of money on the telescope,mount and accessories that we all own, just me personally wouldn’t skimp on the power pack solution either if that’s an option you can choose.yes the lead acid equivalents are a cheaper alternative and are very budget friendly however the draw back is thay don,t like battery drain and don,t hold there charge as well as there LIFo4 counterparts and don,t really have to be recharged if left unattended for 6 mths either depending on the quality of the cell chemistry,I own a tracer uk based high end lifepo4 16ah power bank running my scope and heated dew strap when needed it’s about 75% smaller than celestrons,skywatcher alternative 17ah acid battery power pack. Small, compact easier cable management  and tied via Velcro straps to the side of my fork mount,it also has a shelf life of over 1400+ recharge cycles with a manufactures warranty of 5 years.however if you cannot afford the lifepo4 chemistry stick with acid cell alternative it will serve you well not for years and years on end.

The tracer one is on my radar too, thanks



#8 luxo II

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Posted 07 March 2021 - 08:37 PM

One issue with SLA is that the output may only be a tad over 12V to start with, and  in cold temps the internal resistance increases, and the output voltage drops. While this won't matter for things like heaters, it matters a lot to Synscan handsets which shutdown at 11.4VDC. 

 

One solution to this is to use a DC-DC inverter that will accept a wider range (9-16VDC input) and produces a precise 12V output, these are quite cheap and they're typically 80-85% efficient. Thus the battery output can vary quite a bit without affecting your gear.

 

OTOH I now have a deep-cycle LiFePo which when fully charged is at 13.8V and by the end of a session is still at 13.1V so no risk of the voltage dropping too low.


Edited by luxo II, 07 March 2021 - 08:42 PM.


#9 TelescopeGreg

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Posted 08 March 2021 - 01:19 AM

I have the original (7AH) PowerTank with the SLA battery.  It's certainly not enough to run the setup through a full imaging session, but it's nice for short tests, and during setup / teardown, and has the outlets that everything connects to.

 

The nice thing about the SLA models are those two knobs on the back side which connect directly to the battery.  You can saddle another SLA battery up to them to extend the capacity.  I have a 20-ish AH pack that I built from three 8AH SLA batteries (wired in parallel) that were swapped out from a computer UPS due to age, but still had life in them.  That, together with the base battery, will run the entire kit through a typical 3-hour imaging session with no trouble, and is not very heavy.  For longer runs, I also have a 55ah deep cycle SLA / AGM battery.  Heavy, but good for many hours.

 

Be absolutely sure you are matching battery types (SLA with SLA), and include an in-line fuse.  Don't mix SLA with Lithium, or things could end badly.



#10 CA Curtis 17

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Posted 08 March 2021 - 05:40 PM

If upfront cost is the deciding factor an AGM battery is the way to go.  If the overall cost of useable power over the lifetime of the battery is the deciding factor a LiFePO4 battery wins hands down.  If you need voltage regulation, an inverter, solar charge ready, USB charging ports, etc. then the all-in-one solar NMC power supplies like the ones from Jackery or Maxoak are the right choice.  I did a full write up on battery options/features as part of a review of options for power in the field which you can find on my web site if you care to look.  I put together a set of tables at the end comparing capacities, cost, lifetime etc. for the wide range of choices we have from flooded lead acid to all-in-ones.

 

You can find it here https://www.californiaskys.com/blog

 

There is no one solution which is right for everyone, which is fine since there are options for every budget and desire.  As for myself, I tend to agree with Suprnova 74.  No more lead acid batteries for me as I have finally migrated to a large NMCwith solar panels.  I can image for 8+ hours and be recharged in ~6 hours the next day with a reasonable amount of sun.  Total weight is just 40lbs including the solar panels.

 

Regards,

Curtis


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#11 JMW

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Posted 08 March 2021 - 06:18 PM

I expect to get 15 years or more out of my pair of BattleBorn 50 amp-hour LiFePO4 batteries. I have a 265 watt panel on my truck cap to charge them when away from home. I have a 30 amp Progressive Dynamics charger for when I am charging them at the house. I have been using them for 3 years.

 

I use them independently or together if I fully charge both of them before hooking them up in parallel.

 

I have seven 100 amp-hour BattleBorn LiFePO4 batteries in my Artic Fox travel trailer with 1440 watts of solar on the roof and 640 watts of additional portable panels. I use this much solar so I can run my air conditioner as much as I want without bringing the generator. 

 

I did 10 years of star parties camping in my old converted 5x8 cargo trailer. It was a good fit for my Highlander but the afternoons at GSSP or OSP can be hot some years. I am glad to have the additional living space of my 24 foot long travel trailer with air conditioning.

 

PortableBatteryBox.jpg


Edited by JMW, 08 March 2021 - 06:21 PM.

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#12 Supernova74

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Posted 08 March 2021 - 06:20 PM

If upfront cost is the deciding factor an AGM battery is the way to go.  If the overall cost of useable power over the lifetime of the battery is the deciding factor a LiFePO4 battery wins hands down.  If you need voltage regulation, an inverter, solar charge ready, USB charging ports, etc. then the all-in-one solar NMC power supplies like the ones from Jackery or Maxoak are the right choice.  I did a full write up on battery options/features as part of a review of options for power in the field which you can find on my web site if you care to look.  I put together a set of tables at the end comparing capacities, cost, lifetime etc. for the wide range of choices we have from flooded lead acid to all-in-ones.

 

You can find it here https://www.californiaskys.com/blog

 

There is no one solution which is right for everyone, which is fine since there are options for every budget and desire.  As for myself, I tend to agree with Suprnova 74.  No more lead acid batteries for me as I have finally migrated to a large NMCwith solar panels.  I can image for 8+ hours and be recharged in ~6 hours the next day with a reasonable amount of sun.  Total weight is just 40lbs including the solar panels.

 

Regards,

Curtis

Hi Curtis I feel in the long run will be a wiser decision in the more long term,like I said in previous post folks seem to be very in touch in the latest gadget or accessories for there scopes and keeping tabs on the technology trend lol.i cannot see no reason why powering thease exspensive toys we all own shouldn’t be any different.i replied to a different topic still battery power related tho,I will mention no names as it comes across un professional.puchased a lifeo4 power solution from alliexpress (have you heard that term playing with fire as you just may get your hands burnt) well the reasons why I have mentioned this is why do folks take the risk you don,t really know what the quality is like firstly,a un known name or no name brand from China you really don’t know the quality of the cells,most are not rated as the true AH capacity and can full far short as claimed.no guarantee,impossible to speak to a human being in customer services,is the battery truly safe.enough said anyway I think.



#13 JMW

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Posted 08 March 2021 - 06:22 PM

Here's the inside of my battery box.

 

PortableBatteryBoxInside.jpg



#14 CA Curtis 17

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Posted 08 March 2021 - 08:24 PM

Jeff -  Battleborns are a good choice for LiFePO4 batteries and they certainly will last a long time as they are designed for Marine and RV use with frequent charge and discharge cycles.  Typically LiFePO4 batteries are rated at 2500 or more full discharge cycles.  Lead acid not so much at ~250 to 300.  Nice home built system.  By the way, I will be taking delivery of my brand new 25ft RV this month and will bring it to GSSP, if we end up having a GSSP.  I'll have to keep a look out for you.  Should be able to tell from your battery box.  Maybe next year for OSP.

 

SuperNova74 - I would stay away from no name batteries myself.  Even many on Amazon are not ones that I would take a risk on.

 

Curtis


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#15 JMW

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Posted 08 March 2021 - 09:25 PM

Look for an Artic Fox with a lot of solar on the roof. I am pretty sure I will be the only one there matching that description.

 

I hope the GSSP happens.



#16 astrohamp

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Posted 08 March 2021 - 11:23 PM

I beg to differ on the cycle life of some AGM batteries.  The 100Ah unit I am using certainly looses considerable cycle life if drained to 80% capacity on a regular basis, which I have done on several occasions already.  Although even at this level of very hard operation it's spec indicated cycle life above 500.  Being conservative pulling 50% from the battery can yield in excess of 2500 cycles, and a shallow 20 AH cycle (20%) from the fully charged battery could provide well over 6000 cycles.  This is of course, is according to the manufacturers specification which is what most folks here are reporting for their LiFePo4 batteries.  

Certainly lithium technology has advantages, and in many respects makes for the ideal portable power source.  However, neither battery technology will perform if the operator is incapable of proper use and maintenance.  YMMV


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#17 CA Curtis 17

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Posted 09 March 2021 - 12:42 AM

astrohamp  - I realize that I wasn't precise in my comment.  I should have said, flooded lead acid batteries are rate at ~250 to 300 cycles.  Indeed, AGMs are rated for more cycles, 400 -500 cycles at 80% DOD but not 2500 cycles even if you only discharge them to 50%.   But the more this game is played the less sense it makes to me.  Why buy a battery that you can only use at a fraction of its rate capacity to prevent damaging it?  You can fully discharge a LiFePO4 battery at least 2500 times before you lose 20% of its capacity.  No lead acid battery comes close to that.

 

As I said above, the right battery choice is different for different people.  You cannot beat lead acid on price.  But when you add in life cycles lead acid fares poorly compared to LiFePO4.  And it fares poorly based on capacity per unit of weight, maintenance requirements and safety.



#18 aalmanni

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Posted 09 March 2021 - 11:21 AM

The only "cheap" Lithium power source that I know about is one of the 20Ah Miady Deep Cycle LiFePO4 batteries that are sometimes available on Amazon. I purchased one of these a few weeks ago for just $66 (U.S.) and added a few quick disconnects and a battery box which made the total about $90. It seems every bit as good as one of my 35Ah AGM batteries and weights only about 1/3 as much. Plus, when I purchased my deep-cycle AGM batteries a few years ago they cost $100 each.

 

But, the above only gives me a 12VDC source and so you'll need to spend some additional money to provide regulated outputs at other voltages (which I already had). Also, you may want to get a good Lithium Ion charger to go with the above.

 

I guess what I'm saying is that with your power requirements (3v, 6v, 9v, 12v) you're going to have to pay significantly more for any solution. Plus, the question about AGM versus LiFePO4 is usually one of weight, so if weight is an issue then consider going for LiFePO4. As a general rule of thumb, you'll probably get about twice the runtime out of a LiFePO4 as you would for a similar Ah-rated AGM battery. But, you need to be careful about how a LiFePO4 is rated, since they sometime state a capacity for a lower voltage output (i.e. not 12V).

 

Frankly, unless weight is a significant concern I couldn't see spending five times more for a LiFePO4, unless the LiFePO4 had far greater capacity. 

I looked to the Miady option, the only available models are the 6 and 8AH, the later would be equivalent to the original 7AH, the starting price is not as high as the one I found here locally, my question is how to charge it? using the supplied 15v charger or something special!!



#19 aalmanni

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Posted 09 March 2021 - 12:00 PM

If upfront cost is the deciding factor an AGM battery is the way to go.  If the overall cost of useable power over the lifetime of the battery is the deciding factor a LiFePO4 battery wins hands down.  If you need voltage regulation, an inverter, solar charge ready, USB charging ports, etc. then the all-in-one solar NMC power supplies like the ones from Jackery or Maxoak are the right choice.  I did a full write up on battery options/features as part of a review of options for power in the field which you can find on my web site if you care to look.  I put together a set of tables at the end comparing capacities, cost, lifetime etc. for the wide range of choices we have from flooded lead acid to all-in-ones.

 

You can find it here https://www.californiaskys.com/blog

 

There is no one solution which is right for everyone, which is fine since there are options for every budget and desire.  As for myself, I tend to agree with Suprnova 74.  No more lead acid batteries for me as I have finally migrated to a large NMCwith solar panels.  I can image for 8+ hours and be recharged in ~6 hours the next day with a reasonable amount of sun.  Total weight is just 40lbs including the solar panels.

 

Regards,

Curtis

Your article is very informative, I feel I am enlightened. Thanks a lot



#20 TopherTheME

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Posted 09 March 2021 - 11:58 PM

Battery expert here (no, really!), I'll give my $0.02. 

 

Whether a lithium ion is better vs an AGM or SLA battery really depends on what you want from it. Li brings two big advantages to the table, weight and $/Wh-throughput. Everything else for powering a telescope is a negative. And the $/Ah-throughput is ONLY if you are purchasing reasonable quality cells and not junk from china. That means the cells are sourced from Panasonic, SDI, LG chem, Sony, etc. Your run of the mill high energy AG/NMC622 will get you about 1k full cycles, tops, with about 1-2% calendar aging a year if you keep the median SOC around 50% during storage. If you go with cells that contain Si, then you're looking at about 300-500 cycles, max. If you're purchasing cheap cells from China, with the exception of maybe BAK and a couple others, expect a couple hundred cycles at most. A good quality AGM/SLA battery is good for about 400-ish cycles if you treat it right. That means keeping it near top of charge most of the time to prevent sulfation and keeping it at modest temperatures. 

 

Some of the down sides of Li compared to AGM/SLA besides cost are safety, low temperature operation, more complex electronics (BMS), more expensive charger, harder to recycle, and exponentially higher capacity fade at higher SOC. Li capacity fade follows the Arrhenius relationship for calendar aging and is exponentially greater (approximately) at higher states of charge.

 

If it were my dollars and I wanted to power an AP rig all night, I'd personally go the SLA route. Mainly for safety, low temp operation (gets well below freezing around here), and the fact I like to keep my batteries charged for last minute weather changes (which happens A LOT). But weight is not a big factor for me, it could be for you. 



#21 james7ca

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Posted 10 March 2021 - 02:48 AM

I looked to the Miady option, the only available models are the 6 and 8AH, the later would be equivalent to the original 7AH, the starting price is not as high as the one I found here locally, my question is how to charge it? using the supplied 15v charger or something special!!

The 20Ah Miady comes and goes on Amazon, if you wait another week or two it might come back. As far as I know, none of these batteries come with a charger, so you'll have to buy one of those separately.

 

As for Miady, it's definitely what would qualify as a "cheap" product and I found one review on the internet where someone took one of their batteries apart and concluded that he couldn't recommend it because of the construction and the state of the individual battery cells (they weren't balanced even after a full charge). His comment on the latter is that he didn't think the Miady would last very long.

 

In any case, for just $66 I considered it worth the risk and thus far it has worked well for me. As yet, I only have about 5 discharge cycles on the Miady, but it recharges fairly quickly (I have a 10A Noco Genius charger) and I've run it out to 240Wh on at least two nights (it's rated for 256Wh) and as yet the output voltage have never dropped below about 12.5VDC. At this rate it even seems to have a bit more capacity than my 35Ah AGM batteries.

 

In terms of a getting a certain number of charge cycles, even if the Miady goes for only 100 cycles it will probably still be worth the cost, given that 100 cycles would likely last somewhere between 2 and 3 years (I probably average only about three full nights per month given the weather, where some months are zero and a very few are five or six nights). But, if the Miady goes for 200 or 300 cycles that will probably outlive me (let's be serious, how many are going to be able to use thousands of cycles for just their astrophotography needs).

 

One last thing to note, the Miady runs at just over 14VDC when fully charged and that MAY be too high of a voltage for some devices. In fact, I think most LiFePO4 batteries output higher voltages than do typical AGM/SLA batteries. In my case, however, I use voltage regulators for each of my sensitive devices (like my mini PC and the other computer equipment). In fact, I think that's a good idea even if using AGM/SLA batteries.


Edited by james7ca, 10 March 2021 - 03:26 AM.

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#22 Supernova74

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Posted 10 March 2021 - 11:46 AM

Just to add I think when you consider  thease cheaper alternatives on Amazon,eBay

Alliexspress etc by a fine grain of salt to be honest to there true Ah capacity as you just may find this not to be truly accurate.this goes down to the manufacturing process of the cells,you just get what you pay for to be honest.i used to be into another hobby RC models especially cars,trucks and as the chemistry of the LIFo4 i is very similer or even the same the Chinese counterparts lipo battery just was,nt the same as a well known brand name ie at the time overlander and after very little use the cells started to swell up and then becomes useless and un. Safe to use.ok admittedly I spent the best part of $335 for my tracer 16ah power pack which was not cheap however like I stated in a previous post it’s just not the cost,it’s also piece of mind in very strict quality control environment and vigorous testing which I can assure you the Chinese equivalents most probably don,t go through.and the 1400+ recharge cycle doesn’t even bother me it’s safty and knowing I’m backed up with a 5 year warranty.

 

 


Edited by Supernova74, 10 March 2021 - 11:48 AM.


#23 aalmanni

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Posted 10 March 2021 - 03:44 PM

Thanks everyone, I made my decision, I got the AGM/SLA as it is cheaper to begin with, will experiment on till with various setups and see how it is perform

If I am not satisfied with it, my next replacement would be the LiFePo4


Edited by aalmanni, 10 March 2021 - 03:50 PM.


#24 Spikey131

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Posted 10 March 2021 - 06:05 PM

I have 2 SLA batteries that I alternate to run my dob.  Keep them on trickle chargers.  They were made in 2006, still going strong.


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#25 CA Curtis 17

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Posted 10 March 2021 - 11:36 PM

aalmanni - hope all works well for your application.  As I say, you cannot beat AGMs for up front cost which seems to be your main motivation

 

 

 

Battery expert here (no, really!), I'll give my $0.02. 

 

Whether a lithium ion is better vs an AGM or SLA battery really depends on what you want from it. Li brings two big advantages to the table, weight and $/Wh-throughput. Everything else for powering a telescope is a negative. And the $/Ah-throughput is ONLY if you are purchasing reasonable quality cells and not junk from china. That means the cells are sourced from Panasonic, SDI, LG chem, Sony, etc. Your run of the mill high energy AG/NMC622 will get you about 1k full cycles, tops, with about 1-2% calendar aging a year if you keep the median SOC around 50% during storage. If you go with cells that contain Si, then you're looking at about 300-500 cycles, max. If you're purchasing cheap cells from China, with the exception of maybe BAK and a couple others, expect a couple hundred cycles at most. A good quality AGM/SLA battery is good for about 400-ish cycles if you treat it right. That means keeping it near top of charge most of the time to prevent sulfation and keeping it at modest temperatures. 

 

Some of the down sides of Li compared to AGM/SLA besides cost are safety, low temperature operation, more complex electronics (BMS), more expensive charger, harder to recycle, and exponentially higher capacity fade at higher SOC. Li capacity fade follows the Arrhenius relationship for calendar aging and is exponentially greater (approximately) at higher states of charge.

 

If it were my dollars and I wanted to power an AP rig all night, I'd personally go the SLA route. Mainly for safety, low temp operation (gets well below freezing around here), and the fact I like to keep my batteries charged for last minute weather changes (which happens A LOT). But weight is not a big factor for me, it could be for you. 

You make a very good cautionary point about battery suppliers.  One absolutely must be mindful of the manufacturer of Lithium batteries.  That is why I would always recommend caution with the many unproven Chinese imports.  For LiFePO4 I have confidence in US manufacturers like Battleborn (Sparks, NV) and Lithionics ( Clearwater, FL) who design, manufacture and test their batteries here in the US.  These batteries are fast becoming the batteries of choice for RVs and Marine applications which certainly says a great deal about their capacity, longevity and safety.  AGMs are fast becoming a thing of the past in these markets.  It is enlightening to see how well these batteries are made.  In his video, youtube influencer Will Prowse tears a Battleborn 100Ah battery apart and shows how well it is made.  You can view that here https://www.youtube....h?v=G5E30u-66VI  You can also view his tour of the Battleborn factory.  I have not trouble buying Battleborn or Lithionics, one of which I will do just as soon as my new RV arrives.

 

I believe that LiFePO4 batteries have many more advantages than you give them credit besides weight and life cycles.  The fact that they can be safely fully discharged means that you get the full capacity, not 50% as in AGMs.  One would need 200Ah of AGMs to match a single 100Ah LiFePO4.  That's 120lbs vs 30lbs to carry around.  They only need to be recharged once every 6 months.  As far as safety, you must not be talking about LiFePO4 batteries.  As to the BMS, I consider it a big plus which protects the battery from unsafe operating conditions which an AGM does not have.  And, while an unheated LiFePO4 battery cannot be re-charged below ~32deg it can be discharged below 32deg.

 

Again, what is the best choice for one person may not be the best for another so long as they have the facts when making their choice.

 

Regards,

Curtis


Edited by CA Curtis 17, 10 March 2021 - 11:38 PM.

  • psandelle, jdupton, davidparks and 1 other like this


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