> Hello everyone
> Sorry to dig up an old post but wanted to share some updates. After some
> time and conversing with a few sellers on Aliexpress, I found a company
> that was responsive and honest to my questions. At the time of looking and
> conversing with these folk, Aliexpress/ GTK had an anniversary sale and I
> was able to get a further 15% off my order. I ordered in April a 96v
> 100a/h battery, 10 amp charger, and BMS. The battery and BMS were
> assembled in a nice steel case weighting about 95lbs. I haven't opened the
> case yet but have been told it is a 26s2p pouch cell configuration. The
> BMS is a popular one that frequents ebay/amazon etc, has no display but has
> a bluetooth interface. The app is quite good, I can see all 26 pairs of
> batteries status, 6 points of temperature, a/h draw, lifetime a/h that has
> come out of pack. All in, it cost me about 2050 US to get it to my
> doorstep. Shipping and customs was paid for by the seller. It took about
> 45 days for it to get here, although I was told it would only take 15-20.
> They spent almost 4 weeks before they shipped, and claimed because of the
> sale they were very backlogged. This made me very nervous at the time. I
> did however manage to have payment through paypal, which provided some
> comfort over Aliexpress' unknown to me pay system. At the time, I debated
> building my own pack with Tesla packs as there were some packs on ebay that
> were close in price. Unfortunately where I really wanted 96v I would have
> needed 4 packs which was far more capacity than I needed. I also read that
> the Tesla bus bars could be cut to make it 48v instead of 24v per pack but
> really didn't want to get into that risk. The pack I purchased
> surprisingly has almost the same watt/kg as a Tesla S/X pack, although the
> C rating is much lower.
> So how does it all work? Very well, I am both very happy and surprised at
> the improvement it has brought to my boat. With doubling my pack voltage,
> I was able to discard a chain gear setup to make my prop go fast enough.
> This has significantly reduced noise and vibration. As well, with twice
> the voltage my amps have dropped and my temperatures across all components
> have as well. With the chain system gone, I also had enough room to
> finally employ a water cooling system on my Mars ME-1003, a copper coil
> wrapped around the motor running off a small bilge pump in the outboard
> leg. My temps there are about half what they were before with an auxiliary
> fan. Switching 460lbs of lead acid for 95lbs has made a significant
> difference in range, speed and efficiency. I have been running the boat the
> last 6 weeks and cautiously testing it. I expected about a 1.8x range
> improvement, however it is closer to 2.5x. I have gone 3 loops on my lake
> on one charge and still had 23% SOC left. In the past, measurements of
> power at a outlet showed about 5.6 KW to refuel a lap of the lake (about 3
> miles), now it is taking on average 3.7. The boat is faster with the same
> power applied - 96v 50 amps is 3-4km faster than the old leads at 48v 100
> amps.
> I would say the only fault I found so far with my Aliexpress purchase was
> the standard cord that came with the charger. It was was too thin for the
> charger on hi-mode, got very warm. I replaced it with a heavier cord, no
> issues since.
>
> If anyone has any questions I would be happy to answer them. Thank you
> all on the EVDL that helped!
>
> http://www.evalbum.com/4767
>
> Cheers
> Dan
>
> On Mon, Mar 18, 2019 at 2:00 PM Dan Baker <[email protected]> wrote:
>
>> Thanks Paul. Yeah not quite the same but somewhat similar. I'm
>> assuming that the Alibaba battery would have a higher finishing voltage
>> ~108 volts vs the Tesla pack which would be 24s or 100.8. I should also be
>> able to push a lot more amps out of a Tesla pack if required down the
>> road. I like the fact that the Tesla pack is likely much more configurable
>> as the voltage/ amperage is what I use for BMS/ cell layout but also dont
>> like it for the same reason lol. I can be great to dangerous in my
>> projects. It's down to the unknown turn-key solution vs DIY. using known
>> good (but used) products ,
>>
>> On Mon, Mar 18, 2019 at 12:39 PM paul dove <[email protected]> wrote:
>>
>>> Well, I am not sure you are comparing apples to apples. All Lithium Ion
>>> batteries are not equal in power density or energy density.
>>>
>>> A Tesla model S battery cell goes up to 4.2 volts.
>>> 2modules x 4.2V x 444cells x 2.8Ah = 10.4kW
>>> So 2 x modules of 6s74p (444 cells) =10.4kWh
>>>
>>> While your 96v100ah pack on Aliexpress may be Lithium Iron Phosphate
>>> 96 x 100 = 9.6Kw and may have lower discharge rates.
>>>
>>> On Monday, March 18, 2019, 7:19:01 AM CDT, Dan Baker via EV <
>>> [email protected]> wrote:
>>>
>>>
>>> Thank you everyone for the great response so far. I am still
>>> communicating
>>> with a few Aliexpress sellers although it has been quite frustrating. So
>>> far none have been able to give me any documentation on these packs- cell
>>> type and count, string info, bms used, etc. I have been able to weed a
>>> few
>>> out by reviews and overzealous claims. Product weight seems to be a tell
>>> tale as well, how can a pack weight half as much as other packs and have
>>> the same claimed a/h rating?
>>>
>>> After some more digging this weekend I have found a Canadian seller of
>>> used
>>> Tesla packs. I think I can get 2 x modules of 6s74p (444 cells) from a
>>> low
>>> mileage 2015 P85D for around the same price as a 96v100ah pack on
>>> Aliexpress. I would still have to buy a BMS and likely a charger. I
>>> have
>>> saw some articles on cutting the bus bars and turning it them into 12s37p
>>> packs so I could get 2 x 48v packs and 96 volts total so I can eliminate
>>> my
>>> noisy gear set. I could also buy 4 packs but that would be way more pack
>>> that I need at this time. Anyone ever hack a Tesla pack to make it 48
>>> volts?
>>>
>>> Cheers
>>> Dan
>>>
>>>
>>>
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