36V 30Ah battery from Aliexpress

[Eltommos]

I ordered without checking the number of cells contained in the pack. The Samsung IRN18650 35E cells have a nominal capacity 3500mAh. But there are only 50 cells in the pack arranged as 10S5P which would equate to 17.5Ah not 30Ah as ordered. To achieve 30Ah - 90 cells arranged as 10S9P would be needed.

Rechargeable Electric Bike Scooter lithium Battery Hailong Samsung 18650 Battery Pack 36V 16Ah 23Ah 30Ah Bicycle Lithium Battery| | - AliExpress

After ordering I then questioned the seller on how it's possible to achieve a 30Ah capacity with only 50 cells - the reply back was 'It's achieved with Unique Technology'

I'm aiming to test the capacity when I have received the battery using a Coloumeter and will open a dispute with the seller if as I expect the Capacity is not as described.

I would be grateful for any comment regarding whether it's possible to achieve a higher Ah capacity with any unique technology and also what are my chances of getting a refund if it's the battery is not as described?

I paid using a credit card and may have to request a chargeback if needed.

Note - some negative feedback on Aliexpress for this seller highlights the above issue where this has happened on other orders. I should have read this before ordering.

Many thanks

Eltommos

 

[Bonzo Banana]

You have to be so careful with Aliexpress and only use suppliers which have been on the site quite a few years and have very good feedback and reviews. A common way they misrepresent capacity is to ignore the output voltage and just state the cell capacity by the quantity i.e. 2,600mAh x 50 would be 130Ah but if the batteries were only 5 in parallel the Ah would only be 13Ah at 36V a difference of 10x stated capacity. 3400-3500mAh cells are expensive even in China and they would normally use cheaper cells than that. 2600mAh and 2200mAh are common cell sizes used in better Aliexpress packs which Chinese manufacturers can do well and sell cheaply. If I see a seller selling a 10S2P battery at anything over 36V 6.8Ah I immediately move on knowing that they are dishonest if its using standard 18650 cells.

If I was guessing what capacity cells they were using I would guess 1500mAh for the smallest capacity, 2200mAh for the middle and 3000mAh for the largest pack. So would expect it to be in reality about 15Ah capacity.

I've ordered quite a few battery packs from Aliexpress, most I don't get at all, its fake tracking. Sometimes Aliexpress refunds me, sometimes I do a chargeback. I've never been out of pocket.

You should be able to get a chargeback if falsely described either through paypal or your credit card. If its half its stated capacity I would expect to get half my money back but I've often got the whole amount back but that was on much cheaper battery packs.

 

[Eltommos]

You have to be so careful with Aliexpress and only use suppliers which have been on the site quite a few years and have very good feedback and reviews. A common way they misrepresent capacity is to ignore the output voltage and just state the cell capacity by the quantity i.e. 2,600mAh x 50 would be 130Ah but if the batteries were only 5 in parallel the Ah would only be 13Ah at 36V a difference of 10x stated capacity. 3400-3500mAh cells are expensive even in China and they would normally use cheaper cells than that. 2600mAh and 2200mAh are common cell sizes used in better Aliexpress packs which Chinese manufacturers can do well and sell cheaply. If I see a seller selling a 10S2P battery at anything over 36V 6.8Ah I immediately move on knowing that they are dishonest if its using standard 18650 cells.

If I was guessing what capacity cells they were using I would guess 1500mAh for the smallest capacity, 2200mAh for the middle and 3000mAh for the largest pack. So would expect it to be in reality about 15Ah capacity.

I've ordered quite a few battery packs from Aliexpress, most I don't get at all, its fake tracking. Sometimes Aliexpress refunds me, sometimes I do a chargeback. I've never been out of pocket.

You should be able to get a chargeback if falsely described either through paypal or your credit card. If its half its stated capacity I would expect to get half my money back but I've often got the whole amount back but that was on much cheaper battery packs.

Many thanks Bonzo for your comments. I will test the battery when received and take if from there.

 

[Nealh]

It is buyer beware , chinese sellers have no idea when it comes to mah /ah capacity and will misquote anything.
No generic cased battery can hold 9 cells in Parallel.

 

[Bikes4two]

For the fun of it I bought a 36v 10s 2p battery at a supposed 6800mAh which was clearly bo1*ox but I was curious and at £24 I knew it would be cr*p, but how cr*p?

For a couple of runs I got 2700mAh which I was happy with as that gave me around 15 miles on ECO (I carried it my saddle bag as an emergency tank so to speak) but after a short while it dropped to 1400mAh.

Its now on my work bench for an autopsy - at first glance it doesn't even have a BMS!

I will however be using the batteries for my first efforts with a spot welder, so all is definitely not lost.

 

[egroover]

You can get a 36v 30ah battery in the maximum sized hailong downtube battery using samsung 21700 5000mah cells, here's an example from my usual (and trusted) Aliexpress supplier. Not cheap at £467 tho

Page Not Found - Aliexpress.com

 

[Bikes4two]

@egroover -what do you think it means that the batteries are A Grade? Is that aomething other tban New?

 

[egroover]

@egroover -what do you think it means that the batteries are A Grade? Is that aomething other tban New?

I think A grade are Chinese cells. Brand cells are Samsung/LG/Panasonic. I've only ever ordered my batteries from this supplier with brand cells, and haved checked with Herbert (seller) via messages to check the cells used before purchase