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Old 10-31-2018, 12:07 AM   #1
ratdude747
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Default Chinese SLA's: Any good?

I'm looking to replace 3 dead/missing 12V 8ah SLA UPS batteries.

Are the cheap chinese ones on ebay generally any good? Or are they garbage like I remember chinese Li-ion batteries being in years past?
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Old 10-31-2018, 06:18 AM   #2
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Default Re: Chinese SLA's: Any good?

well it's a simple thing, i cant see them getting it wrong.

as for the Li-ion, there are good ones.
you just need to know which ones, so you want ones that look like industrial cells.
all the "fuckery-Fire" cells etc are recycled from old junk.

this guy has some good vids on the subject of avoiding the bad ones.
https://www.youtube.com/channel/UCQa...B_Kd54g/videos
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Old 10-31-2018, 11:05 AM   #3
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Default Re: Chinese SLA's: Any good?

Getting good purity lead plates is still kind of important in SLA's...
I had a few china SLAs that died after a year, unsure if it was due to the UPS charging them or not, YMMV...
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Old 10-31-2018, 11:26 AM   #4
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Default Re: Chinese SLA's: Any good?

well yausa's used to only last a couple of years when i worked with alarm panels.
i think they dry out from the warmth of the housing / 24/7 charging.
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Old 10-31-2018, 11:26 AM   #5
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Default Re: Chinese SLA's: Any good?

I find chinese brand SLA's don't last very long. You can see the plates are poorly made, like mashed potatoes that look rusty.

Panasonic SLA's are very good but made in china. Digikey seems to be only selling "B. B. Battery" now.

8Ah is oddball, it might be a 7Ah with "generous" specs?
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Old 10-31-2018, 04:06 PM   #6
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Default Re: Chinese SLA's: Any good?

There is certainly a risk of poor QA like any Chinese products but I've had decent luck with them.

My UPS came with Yausa's which lasted a little over 2 years, the first set of Chinese off-brand batteries lasted 3.5 years and the second set have a little over 2 years on them and are still going strong. Not bad considering the Chinese batteries cost less than $30 a pair and Yausa's would have been around $40/ea.

SLA's in general don't seem to have a spectacular lifespan, especially in UPS's which tend to "cook" the batteries with constant trickle charging and close proximity to hot electronics.

Last edited by dmill89; 10-31-2018 at 04:08 PM..
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Old 10-31-2018, 06:27 PM   #7
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Default Re: Chinese SLA's: Any good?

I find UPS's have high float voltages because the chargers are basic and do nothing for correction on ambient heat.

Somewhat depends on the SLA manufacturer. For high discharge PbCa url=http://www.power-sonic.com/phr_series.php]Powersonic[/url], Yuasa: 13.65V at 20C down to 13.45V at 30C, Panasonic: 13.6-13.8V at 25C/77F
I go with around 13.5V and they don't dry out as fast.

Battery prices seem to have really lifted off, it's almost cheaper to just buy a new UPS.
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Old 10-31-2018, 07:20 PM   #8
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Default Re: Chinese SLA's: Any good?

i wonder why we arent seeing ups's with lithium in them yet.
the charging chips are very evolved and cost literally penny's
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Old 10-31-2018, 07:23 PM   #9
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Default Re: Chinese SLA's: Any good?

The lithium batteries themselves have not plunged in prices...

and a UPS does not need to be lightweight... something needs to weigh down the paper.

---

Cost analysis here.

Let's say Peukert's law doesn't apply to Li-ion. SLA gets about half capacity at typical load, so we can cut our capacity about half.

My crappy UPS: It uses three 6V 12Ah packs for a total of 216 watt-hours. You can buy cheap chinese SLA batteries for about $16 a piece for a total of $48.

Now Li-ion. Say we're optimistic and only need 108Wh. At 3.7V, we'd need 29 ampere-hours. Add about 10% for losses due to protection circuitry and other stuff. And say we're using 18650s at 2.5Ah a piece. Mind we need very low ESR cells. Anyway that comes out to about 12 cells, and at $8 a piece that comes to about $96 in batteries.

That's double. Plus if you don't use it at full capacity, the SLA version will last longer and you'll get closer to the full 216Wh capacity...

Simple economics wins again

Last edited by eccerr0r; 10-31-2018 at 08:52 PM..
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Old 10-31-2018, 10:30 PM   #10
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Default Re: Chinese SLA's: Any good?

Quote:
Originally Posted by eccerr0r View Post
The lithium batteries themselves have not plunged in prices...

and a UPS does not need to be lightweight... something needs to weigh down the paper.

---

Cost analysis here.

Let's say Peukert's law doesn't apply to Li-ion. SLA gets about half capacity at typical load, so we can cut our capacity about half.

My crappy UPS: It uses three 6V 12Ah packs for a total of 216 watt-hours. You can buy cheap chinese SLA batteries for about $16 a piece for a total of $48.

Now Li-ion. Say we're optimistic and only need 108Wh. At 3.7V, we'd need 29 ampere-hours. Add about 10% for losses due to protection circuitry and other stuff. And say we're using 18650s at 2.5Ah a piece. Mind we need very low ESR cells. Anyway that comes out to about 12 cells, and at $8 a piece that comes to about $96 in batteries.

That's double. Plus if you don't use it at full capacity, the SLA version will last longer and you'll get closer to the full 216Wh capacity...

Simple economics wins again
^This, there are a few Lithium-Ion UPSs now but they are very-expensive compared to their lead-acid counterparts:

Examples:
$350 for a basic 300W home unit: https://www.newegg.com/Product/Produ...5640-_-Product
$1,550 for a 1000VA/900W Rack-Mount Unit: https://www.newegg.com/Product/Produ...4550-_-Product
$2,300 for a 2000VA/1800W Rack-Mount Unit:https://www.newegg.com/Product/Produ...5979-_-Product
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Old 10-31-2018, 11:21 PM   #11
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Default Re: Chinese SLA's: Any good?

I'm trying to collect a boatload of old weak 18650s, I wonder how many I'll need to make a substantial pack I can use for a UPS...

... or to counter the demand hour electric rates I have to deal with now. Charge batteries during cheap times, use during peak...
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Old 11-01-2018, 12:07 AM   #12
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Default Re: Chinese SLA's: Any good?

12V 7Ah SLA chinese goes for USD $25 so $50 for two, lasts 2 years = $0.07/day cost of ownership
12V 7Ah SLA Panasonic USD $45 so $90 for two, lasts 3 years = $0.08/day cost of ownership
12V 7Ah LiFePO4 goes for USD $150 so $300 for two, lasts 6 years = $0.14/day cost of ownership

Silicon Chip magazine May 2018 did a DIY UPS using LiFePO4 batteries. It looks good but they are an expensive battery.
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Old 11-01-2018, 04:58 AM   #13
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Default Re: Chinese SLA's: Any good?

Quote:
Originally Posted by eccerr0r View Post
I'm trying to collect a boatload of old weak 18650s, I wonder how many I'll need to make a substantial pack I can use for a UPS...

... or to counter the demand hour electric rates I have to deal with now. Charge batteries during cheap times, use during peak...
Here is a place that you can buy used batteries from

https://www.ebay.com/itm/99-SANYO-18...ry!32220!US!-1

I have not tried these before from this seller because I do not like to use “used” cells because from what this seller has as a disclaimer is the number one reason I do not buy them

I do like this seller because they seem to be honest about the really of buying these types of
( pack or cell )

Now if you have a lot time ( to test and group similar milliamperes batteries together) and want to save money this would be the way to go

Now I will buy batteries that the seller says that were out of NEW equipment or NEW battery pack I have tried and tested them and one in while have got a bad battery here and there
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Old 11-01-2018, 08:31 AM   #14
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Default Re: Chinese SLA's: Any good?

Eh... no thanks if they've already been individually tested as bad
Thinking more of getting used packs that have group tested as bad... and at a cheaper price than that...
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Old 11-02-2018, 12:55 AM   #15
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Default Re: Chinese SLA's: Any good?

BTW, just like li-ion cells, SLA's need to be replaced as a group else you may run into interesting problems.

No fires however, even without a charge controller -- just poor performance and possibly another premature replacement...
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Old 11-02-2018, 07:02 AM   #16
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Default Re: Chinese SLA's: Any good?

maybe use the newer battery tech intended for solar banks - although it costs more.
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Old 11-02-2018, 10:00 AM   #17
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Default Re: Chinese SLA's: Any good?

Name of the game for UPS (AND solar power banks!) is to reduce costs...

LiFePO4 due to its apparently good cycle life even when discharged to near empty might be beneficial because both Li-ion and SLA cycle life will go down if subject to the same...

But still 2000 cycles is only a couple of years. And SLA/Li-ion will survive that long if you size them properly.

UPS use is just miserable however. Different story indeed.
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Old 11-02-2018, 07:54 PM   #18
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Default Re: Chinese SLA's: Any good?

Quote:
Originally Posted by ratdude747 View Post
I'm looking to replace 3 dead/missing 12V 8ah SLA UPS batteries.

Are the cheap chinese ones on ebay generally any good? Or are they garbage like I remember chinese Li-ion batteries being in years past?
Ah! You mean those chinese Sandium's?
https://www.youtube.com/watch?v=KFJUPZ0pkog

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Old 11-02-2018, 10:14 PM   #19
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Default Re: Chinese SLA's: Any good?

hooboy...
what can be trusted these days
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Old 11-03-2018, 12:42 AM   #20
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Default Re: Chinese SLA's: Any good?

If you have lots of 18650 cells recovered from laptops just build a pack add a controller and use them up.
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