Anyone ever try these ebay 36v 8AH Li-ion batt packs?

[1000watt]

I would be using this with an e-bike kit 500w 36v rear hub motor and infineon 36-48v [22 Amp] Controller.

item number: 300338328824
$249.99


More info off ebay add:
About Li-Ion battery Module: 36V 8.0Ah ( 288 Wh) with PCB ready (40 x 18650 10S4P):

Describe
# * 36V Li-Ion Battery pack is made of 40 pcs 2000mAh Li-Ion 18650 Cell and packed by 10 pcs of 3.6V 8000 mAh Cells parallel with 4 3.6V 2000mAh cells
# * One Special 10 cells BMS with equilibrium function installed in battery pack to protect battery from over charger, overdischarger and over drian
# * Voltage : Peak - 42V working - 36V
# * Capacity: 8.0Ah
# * Energy: 296Wh
# * Cut-off voltafe: 26V
# * Max. discharging current: 30amp
# * Continue discharging current: 20amp
# * Two terminals from the pack:
# One cable with DC barrel connector(5.5mm OD, 2.1mm ID) for charging - 6" long 18 AWG wire
# One terminal is for discharging: - 12" long 14 AWG silicon pre-wire with TAMIYA connectors for connecting to your device
# * Please choose our ( 2A ) 36V Smart Li-ion battery charger to charge this 36V battery pack. The charging time is about 5 hours for this 8.0Ah battery pack
# * Dimension: 7.3" L x 2.6" W x 3.7" H
# * Weight: 4.6 LBs
# * Applications:
# o RC Robot: to drive DC motor < 1600 W
# o e-bike
# o It can be used an internal pack to drive 36V DC motor to achieve faster speed and power for RC toy

Size: 7.3" x 2.6" x 3.7"

Net Weight: 4.60 lbs

About Li-Ion 18650 Cylindrical Cell 3.6V 2000mAh Cell:

Describe
# 3.6V 18650 size Cylindrical Li-Ion Cell.
# High capacity: 2000mAh.
# Working Voltage 3.6V and Peak Voltage 4.2V.
# No Memory effect and longer storage life than NiMH Battery.
# Lighter weight and higher energy density than any rechargeable battery.
# Perfect for building RC Car, RC airplane, Laptop battery and other portable power devices.
# Dimension: 18 mm diameter and 65 mm Length.
# Weight : 50g
# Max. Charging current: 1C ( 2.0A )
# Max. Discharging current 2.5C ( 5A )

Size: 65mm x 18mm x 18mm

Net Weight: 1.76 oz

Caution
Li-Ion Battery may explode if charging or discharging inproperly. User must have knowledge how to charge and discharge Li-Ion battery before making a Li-Ion Battery Pack.
Strongly suggest that you use a protection IC to keep battery from over charging.

Tips
The most of lap-top computer batteries uses 18650 cell inside battery. If you try to fix your old battery, please choose this Li-Ion 18650 cell.

About 36V 2A Li-Ion Battery Charger:

Describe
# Intelligent charger designed for all types of 36V/37V (10 3.6V Li-Ion/Li-Polymer cells / 12 3.2V LiFePO4 cells) Li-Ion Battery packs including Polymer LiFePO4, Polymer Li-Ion and Cylindral Li-Ion.
# Worldwide input AC power from 110V - 240V.
# 2000 mA (2.0A) constant charging current for faster charging, save your much more time.
# Charging time for 4000mAh battery pack is about 2.5 Hrs. ( Please don't use it to charge Li-Ion battery with capacity < 1800mAh).
# Built in IC to cut off power automatically when battery is fully charge.
# Red LED will show Battery in charging and Green LED shows full. (Green LED is also on without battery).
# DC connector(OD 5.5mm, ID 2.1mm) with 30" long prewire is for connecting to battery pack.
# Compact size and light weight. It is perfect for charger a 36V / 37V Li-Ion battery pack module.

Size: 6" x 3 1/4" x 2"

Net Weight: 15.50 oz

Caution
Only charge Li-Ion battery pack with capacity > 1800 mAh. Don't use the charger for lower capacity Li-Ion battery pack.
Only charge Li-Ion battery pack with voltage 36 V/ 37 V ( 10 3.6V/3,7V Li-ion/Li-Polymer cells / 12 3.2V LiFePO4 cells pack ).
Don't use the charger for Lower voltage battery pack, whcih may cause battery exploded.
Wrong voltage setting may cause battery exploded.
We are not responsible for any damage caused by user and misusage.

 

[neptronix]

Looks like 1 person bought it so far. But you can't contact that person to find out if it is working for them ( eBay seller disabled that ability ).

8aH is a small capacity for a 500w setup by the way. Expect about 10 miles , maybe 15 if you pedal a lot.

Sounds like a gamble to me. A lot of these cheaper packs have issues.. IE shitty BMS that makes them worthless.. shitty charger that doesn't last.. not honest about the cell's specs, etc.

You are obviously looking for something cheap, so you might want to consider LiPo packs. You can get 10ah of 36v zippy/turnigy packs for about $200 shipped. A reliable smart charger, power source, and some parallel/serial connection hardware would run you about $200 in total as well shipped.. then you can add battery in 5ah increments for $100 shipped.

Forget about these eBay batteries with no reputation!

 

[John in CR]

When I bought my Ping packs over 2.5 years ago, that was an Ebay battery with no reputation and the cheapest packs available. Sure there's a risk purchasing anything directly from China, but to dismiss them all is a mistake.

 

[yopappamon]

That charger has the same case as the one I got from Terry at hightekbikes.

 

[auraslip]

http://victoriz.com/

I got the site of the label on the battery.

It looks as if they build packs in house in America. This is really cool! They actually have pictures of the product you'll receive! They also build ebikes. Looks like I see a magic pie on one of them

At $250 you have reason to be leery. These are probably cheap no name cells that may or may not be taking up room in their warehouse.


On the other hand, they are only twice the price of a 36v12ah sla kit and will give you the same range at a fraction of the weight and last you quite a bit longer.
I'd ask about the manufacturer of the cells, their age, and the manufacture of the BMS. For a first kit, they'd be much better than SLA.

 

[dogman dan]

Based on the size alone, I'd say good for a bafang on a 15 amp controller, but not a 9c on a 20 amp controller.

But I could be wrong, since I have no idea of the chemistry, or c rate of the cells. My guess is 400 watts yes, 800 watts no.

If 8 ah is all you need, you might go for 4 6s lipo packs from HK. 12s will get you a bit more pep, and still be pretty simple for a lipo setup. Cost pretty cheap still, but a few bucks more perhaps. You could go with a starter setup of just 5 ah if that is not too short range.

 

[auraslip]

Out of curiousity dogman, how many amps does a small hub motor use WOT at 36v?

I'm thinking of building a bike for my family, and I'm planning the cheapest route possible. I'm thinking a geared motor from cell_man....and maybe SLAs....but only if I can find a motor that draws less than fifteen amps....

 

[neptronix]

By the way, i have the 250w cell_man kit. It draws 17a or 503w at peak.
The 350w setup will more likely draw the usual 20amps then at peak.

Remember, peak amps are usually drawn at the lowest part of a motor's rpm range. So, cruising amps are quite a bit less.

 

[heathyoung]

There is someone selling those same cells pre-welded on ebay Aus as well. They don't know what they are selling (ie. the comment about using these cells in a laptop - completly the wrong chemistry / terminal voltage). I wouldn't be using them on anything that draws reasonable current, or the lifespan will be very short. Notice that they did not specify capacity (or lifetime) at C rate.

 

[1000watt]

# * Voltage : Peak - 42V working - 36V
# * Capacity: 8.0Ah
# * Energy: 296Wh
# * Cut-off voltafe: 26V
# * Max. discharging current: 30amp
# * Continue discharging current: 20amp

 

[heathyoung]

Not quite:

Capacity @ 1C = 2000mah
Capacity @ 2C = 1750mah
Capacity @ 5C = 1200mah

etc...

Lifetime = 2000 cycles @ 50% DOD, 1000 cycles @ 75% DOD etc.

Not likely from an ebay seller, but capacity at 2 or 3 C would be useful especially with small format cells.

 

[Jeremy Harris]

Not quite:

Capacity @ 1C = 2000mah
Capacity @ 2C = 1750mah
Capacity @ 5C = 1200mah

etc...

Lifetime = 2000 cycles @ 50% DOD, 1000 cycles @ 75% DOD etc.

Not likely from an ebay seller, but capacity at 2 or 3 C would be useful especially with small format cells.

These are lithium chemistry, so their Peukert factor will be close to unity. The above sort of characteristic might be typical for lead acid cells with a fairly high Peukert factor but frankly I've never seen much change in capacity with discharge rate with lithium cells, even the really cheap ones. Generally, even some of the higher end manufacturers don't bother to give this data, as it's a given that cells that are discharged within their maximum ratings will deliver pretty close to their rated capacity.

Whether or not these packs are OK and value for money really depends on how well they are put together, rather than how good the cells are, I suspect. Personally I'm a bit leery of using packs made from lots of tiny cells like this, having seen some of the really appalling workmanship inside some that have been taken apart on here. All those cell interconnections are potential failure points under shock and vibration, as others have found with packs from suppliers like Cammy on ebay.

Jeremy

 

[auraslip]

Looking at the pdf from justins lead free talk makes me agree with the sentiment about poorly made packs of small cells. Lots of room for fiery explosive error.