I just bought 2 new 48v 80ah batteries

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They are 48 volt 80,000mah ( 80ah ) batteries ( They said they were 100ah batteries ) but their math is wrong.
Samsung Cells and they each come with battery charger. It will take 4 to 6 weeks to get them from china. :LOL:
Bought these batteries on Ebay. I hope these batteries work well. I get a small tool box to put them
in and bolt the tool box on my rear flat rack.;)
BATTERY.jpg
 
Using that XT60 battery connector (Yellow) for scale, it seems unlikely they are 80Ah batteries. Even with Samsung 21700 50e/s batteries, which are 5 Ah each, that would require a whopping 16 in parallel and then 13 of those 16 parallel groups in series to hit that 48V 80 Ah figure.

I did a disassembly of an eBay battery advertised as 48v 30Ah, and discovered it was a 13s4p layout. Or 48v 20Ah. Ebay sellers frequently have a disconnect with that funny thing called the truth.

Here is a picture of my battery's guts, which is 1/4th of the capacity stated by Your Seller.
Also a picture of the advertisement, which shows the XT60 connector as a size reference with the pack. The cells were a very snug fit in the case.

48V 30AH 21700 panasonic battery 30AH 30A BMS.jpg

13S4P 5Ah per cell 20 Amp hour max.jpg
 
That doesn't even sound realistic and I don't know a whole lot about these batteries but what I do know about things in general, batteries of any kind included, is; if it sounds off, it most likely is and this sounds way off just based on the pricing. I don't think a battery of this type exists that's any good for less than $200 to $250 for a real 48 volt 10 to 15 aH battery. If what they claim were even able to be true, those things would be best sellers and highly rated by everyone and would probably put most of the reputable battery companies out of business and I don't really see that happening. Just my .02
 
Well if you every been on the Alibaba website you can see these type of batteries. They told me in a email that they use Samsung 18650 cells.
Now I will check it out the batteries when I get them from china. I will let you guys know after I check out the batteries. Now I will agree with you ebike batteries are twice the price here in the states. That is why I get from china. Alot cheaper from china. Granted it take 4 to 6 weeks to get my batteries lol. I don't care I live Oregon It snows here that is why I'm in no big hurry to get them. ;)
 
Your first step will be to "weigh" the battery pack upon arrival. If you can, use an accurate postal scale. Then look up how much an 18650 cell weighs. Divide the total weight of the battery pack by the weight of a single cell. Round down to get your total number of cells. Then divide by 13 (it requires 13 cells in series to get to 48v). So, if your result after that is "3", that is how many are in parallel. The final number will need to be about a 20 plus number to be the stated 80 Amp Hours of capacity.
 
On one hand, I would love to use bargains like these.

On the other hand, I would just be too afraid of the safety of my family.

Give some thought to how/where you are going to store those batteries.
 
I bought a second battery for Ariel Kepler. 52 volt 20ah. Knew I was taking a chance but…Anyway my sole test was riding comparison with the original with my big self. Same performance with my big self. $400 including a better charger than the original. Fits original bracket perfectly. I only point this out by way of comparison price wise. Hope it works well for you.
I bought it from a guy called OnWeGo on aliexpress. Apparently I was really lucky.
 
I purchased 2 batteries on AliExpress. They were advertised as 27ah. Load tested out as 15ah. But I knew going in that they were falsely advertising the AH based on reviews. Also just based on the $ you know they are BS. Used them on two 48v 500w e-bikes as a 2nd battery and they worked perfectly fine. You just have to know going in that they’re not going to be as advertised. Probably the only seller on AliExpress that legitimately rates their batteries is UPP. I just received a 52v 24ah LG4800 cell battery from them for $420 but haven’t tested it yet.
 
JerryB said:
When those batteries arrive.....up your fire insurance or make sure they are never charged indoors........I would not trust them but that's me.
Click to expand...
Well I have the same concern but they are Samsung 18650's. I do trust Samsung. I will be cautious.
 
Well I just got my 2 batteries from china. I can't test my batteries for AH till I get a new Volt meter. My is dead :(
I borrowed a friends volt meter at it did not have a AH setting. Now the batteries we at 51.4 volts and not fully charged.
I will have new OHM meter next week on payday.

Here is some More Info:

Size: 9.5 inches long by 2.5 inches. wide.
weight is approx: 3 lbs.

I am charging the batteries now.

That is all I know so far. I will follow up when I get a new Volt Meter
 
Hozer said:
Well I just got my 2 batteries from china. I can't test my batteries for AH till I get a new Volt meter. My is dead :(
I borrowed a friends volt meter at it did not have a AH setting. Now the batteries we at 51.4 volts and not fully charged.
I will have new OHM meter next week on payday.

Here is some More Info:

Size: 9.5 inches long by 2.5 inches. wide.
weight is approx: 3 lbs.

I am charging the batteries now.

That is all I know so far. I will follow up when I get a new Volt Meter
Click to expand...
You need a device that puts a constant load on the battery to figure out the AH capacity. Something like this.
DL24MP 600W Car Power Electronic Load Voltage Indicator Battery Tester 18650 Pack Capacity Monitor USB DC 72V Checker Tools
 
At 3 pounds of weight, they are likely 6 to 8 Ah of capacity each pack. You must have a certain number of batteries to produce amp hours at 48 volts.
My 20 Amp hour battery (at 48 volts) weighs 9.4 pounds, with about a quarter of that pound being the plastic shell. The battery I have uses Samsung 21700 50e cells.

Multimeters don't have an "amp hour" setting on any of them, as it is a totalized figure over an hour. If you try to measure the "amps" of your battery you will blow the fuse in the meter, and possibly damage your packs. If you put an Ohm Meter across the battery, you will damage the Ohm meter.

How you measure your Amp Hour figure is as follows:
1. fully charge the batteries.
2. put a known load across the battery, something which draw about 6 amps of current for a pack your size.
3. Keep track of how long the battery is delivering 6 amps of current. Don't let your battery pack voltage drop too low.

If the pack can deliver 6 amps for 1 hour, it is a 6 amp hour pack.

If the pack can deliver 4 amps for 1.5 hours, it is a 6 amp hour pack.

If the pack can deliver 10 amps for 3/4 of an hour, it is a 7.5 amp hour pack.
 
Based on the dimensions it’s a 12s3p battery. If cells are 3500mah it’s 10.5ah battery. But you really won’t know until you load test it. Or pull the shrink wrap and get the model # from the individual 18650 cells.
 
hsdrggr said:
Based on the dimensions it’s a 12s3p battery. If cells are 3500mah it’s 10.5ah battery. But you really won’t know until you load test it. Or pull the shrink wrap and get the model # from the individual 18650 cells.
Click to expand...
Based upon the "bumps" in the shrink wrap, I am leaning towards 13s3p. Otherwise, it won't be a 48v pack.
The amp hour figure I guessed, is based upon the weight.
 
addertooth said:
Based upon the "bumps" in the shrink wrap, I am leaning towards 13s3p. Otherwise, it won't be a 48v pack.
The amp hour figure I guessed, is based upon the weight.
Click to expand...
Ok I counted 28 cells. I went to rapid Tables to see if it was correct.

This is how I came out to the Amp Hours.

I used Rapid Tabels at https://www.rapidtables.com/calc/electric/mah-to-wh-calculator.html

80000mah to watt hours = 3840 watt hours.
to get the amperage you divide the voltage by watt hours.

So 3840 watt hours divided by voltage ( 48 volts ) = 80ah

Now I won't be sure unless I get a load on the batteries. I will get a Volt meter next week on payday.

cya
 

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