Sunthing-28 Lithium Ion Reviews?

Anyone have good luck with them? I read a lot of good things about LiFePO4 batteries from Sunthing-28 but I can't find anything about the Li-Ion. I'm specifically looking at the 48v 12Ah linked below.

Follow up question, will this battery work OK with a MAC 350w front hub motor and 25A controller? Thanks.

http://www.ebay.com/itm/48V-12AH-Battery-Li-ion-Battery-Aluminum-Case-BMS-Electronics-Charger-Recharge/132032987507?_trksid=p2047675.c100005.m1851&_trkparms=aid%3D222007%26algo%3DSIC.MBE%26ao%3D2%26asc%3D40757%26meid%3Db34cce610b57439da0f4011f97a8f15d%26pid%3D100005%26rk%3D2%26rkt%3D6%26sd%3D142198166829

You have a "MAC 350w front hub motor and 25A controller and are looking at a battery as follows. 350 watts/48V is 8 amps. So yes, it would work ... as the "Maximum continuous discharge current: is15A. But ... "cycle 500 times" is awful, and " Li-ion" is non-specific - we don't know what the chemistry is. And its from eBay. So its all a gamble. You'll get maybe a year from it, charging daily. Better to spend money getting double to quadruple the cycles with a better, more expensive battery.

Please do not put the battery for more than 500W motor
48V12AH Li-ion Battery Specifications ：
Type : 48V12Ah Li-ion battery pack (with alu case)
Model: EMC4812001
Nominal voltage: 48V
Weight: about 3.5kg
Standard Charge (0-45 ℃): Use 3A constant current charge to 54.6V ,and use constant voltage charge to the current less than 100mA
Standard discharge:3A constant current discharge to 36.4V
Fast discharge: 5A constant current discharge to 36.4V
Nominal capacity: 12Ah (standard discharge)
Cycle life: Standard charge and fast discharge cycle 500 times , the capacity will not less than 60% of the nominal capacity .
Maximum continuous charging current: 5A
Maximum continuous discharge current: 15A
Maximum instantaneous working current: 20A
Resistance (23 ± 2 ℃): ≤ 250mΩ
Battery case: Whitebait Aluminum Case
Protection system: Internal BMS
Charger: 54.6V / 2A
Size: 385 * 110 * 75mm
Storage conditions: -15 ~ +35 ℃, relative humidity: 45-75%, atmospheric pressure: 86-106KPa

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It's not a strong battery. Suitable only for low wattage setups. At that price, it will have less than stellar cells in it, as the specs show. Max amps is less than 2c.

But if you have a 350w system, are not 250 pounds, and don't ride up long steep hills, it would work. Cruising 15 mph well within this batteries capability. But a long 20 mph ride would work it hard.

However,, a 25 amps controller is way beyond 350w. It can easily kill that battery I'd think. Just leaving a stop sign without pedaling will hit it with 1000-1200w.

Thanks for the advice guys. Are the batteries at bmsbattery any better? Any other decent quality batteries at a low price? Looking for a good value battery that will perform well with the MAC 350w and 25A controller.

If I needed eBike pack in USA I would look at Luna battery packs. I haven’t ever used their packs but I’ve bought other items and they provided excellent email service for an issue I experienced with my BBS02. I never got the impression they were avoiding or ducking my service ticket. Quite the contrary, they quickly answered (email) every step of the way and then followed up to make sure everything worked out satisfactorily in the end.

Problem with out of country battery pack vendor is what happens if there’s a warranty issue? Shipping is a major hurdle. BMS Battery? Oh no… They can barely translate English. EM3EV builds damn fine packs but again, what if there’s a need for warranty service/replacement? How’s shipping going to work?

At least in USA, Luna pack can be return shipped via ground. And if it’s defective, I’m convinced they’ll work very hard to make it right in as short amount of time and as little inconvenience as possible.

How does return shipping work? People have been unable to return if they declare their package a battery. Mention the idea of return for repair and all bets are off with UPS. Some resellers do all they can to avoid shipping returns and repairs. It's ridiculously expensive. UPP in China sends BMS for self repair, just like your recommendation. For 30 days you have full coverage, but Aliexpress gives me that with top rated resellers like Unit Pack Power. My UPP BMS is identical to the past warranty BMS on my friends Recommended battery supplier. The other builder you mention has a warranty station in the USA last I heard. Am I wrong? In the past I was critical of UPP, EM3ev and other similar models, but I was wrong . Empoweredcycles, California eBikes, are good resources too.

Nothing has changed that dramatically, you still get what you pay for.

If you are in the USA,, it's not possible to ship back a battery that is known to be defective without the customer taking a huge risk. US shipping rules, it's not come get me, I'm in china, for the customer.

Would a legit vendor ask a customer to do that? This is the catch 22 of lithium,, a battery with known defects cannot be considered to be still certified under UN 38.3, supposing it ever was. This is why if there are problems that can be fixed by a customer with moderate skills, the vendor ships you a new bms, or a few new cells. If a battery under warranty is bricked, then they have to eat the entire loss.

The key to making it can be selling batteries that don't fail early. However, the customer has to cooperate by not flogging the thing to death. If the specs say 30 amps max discharge, it's not going to run a 3000w motor system.

“Defective” is a key word - just last week my post office assured me I can ship most if not all of my “good” RC Lipo to CA from NY. I’ll be moving back to San Diego full time. The window guy said not to seal the box so they can inspect and be assured there’s enough bubble wrap protection and not too much in one package for ground carrier only.

We shall see? I’ll report back when the deal is complete or suffering further complications? I also intend to carry-on a few for my flight but the largest quantity will attempt to go USPS. If that fails, some of my coworkers will be getting some free good RC Lipo...

Battery pack shipping is a conundrum and that is why I mentioned I would probably buy a Luna pack (if I needed a pack) because I can drive it myself 110 miles up to LA and sort out anything that might need to be sorted out?

I guess the only legit thing someone can do is to just not buy a battery pack with much hope or expectation of any warranty? Maybe local only?

One more reason I’ll just stick to cheap hobby cells... Ship a few at a time as fully disclosed and as legally possible, of course.

Yes,, in small enough size,, good lithium ships without a big problem. Totally legal to ground ship small sizes. Big pack, like 500wh is another thing. I'm not sure what the limit is now for size. That guy at the window might have been thinking you were talking about smaller packages than you were thinking.

100 wh goes on a plane still I think. so ground mail may take more.

Big pack you just declared defective,, no legit vendor want's it to have his address on it when it burns a truck down.

Cheap batteries are a gamble. Victpower , bmsbattery , lots of ebay stuff. Gamble ? go to the track pick a horse. When you lose on a battery you lose it all .
You mac needs double the power of that batteries weak cells.

50v x 30 amps = 1,500 watt so you need a 1,500 battery.
40v x 30 amps = 1,200 watt so you need a 1,200 watt battery.
That battery only go for 15amps. It wouldn't last.
Remember voltage spikes.

FWIW,, I have a cheaper cell 48v 20 ah pack. It runs great on my 22 amps controller,, if I add a second 13 ah battery in parallel with it.

It does ok,, not well but ok, by itself with a 22 amps peak, and cruise load of around 15 amps.

So unless you pay a lot for it,, you are not getting good enough cells in there to pull 30 amps, on a small size pack.

tomjasz said:

How does return shipping work? People have been unable to return if they declare their package a battery. Mention the idea of return for repair and all bets are off with UPS. Some resellers do all they can to avoid shipping returns and repairs......

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I went through my own hell with this, which I've posted on, as have others. Its this awful state of affairs that suggests people buying batteries should do their research first and buy with confidence. Only buy batteries where the cell used is fully disclosed and standard spec sheets are available so you know what you're getting, and there is a warranty available. Its the old adage - buyer beware!

Quick follow up, Post Office accepted my well packaged 8qty 5Ah 4S packs and 1qty 5Ah 6S pack for ground shipment NY-CA.

Dad sent me Honey Baked Ham for Christmas so I used that serious styrofoam container and sturdy box. Everything wrapped well in bubble wrap and fortunately got the same counter guy I’d asked couple weeks ago.

Most interesting question “are the batteries installed in equipment?” “Um, no just bubble wrapped and leads covered to prevent short circuits.”

Apparently can’t be over 11lbs if the Lithium ion cells are NOT installed in equipment. Fortunately, I was about at that weight so he looked in and said it was packed well. Told me to seal it up and pay $37.25 - OUCH but I guess it’s still cheaper than buying all new RC Lipo back in CA?

I believe the important thing besides good solid packaging is/was declaring them so that the shipment can avoid passenger aircraft?

If I had to ship a commercial eBike battery like a Shark, Dolphin or Alloy pack I would then say the batteries are installed in the equipment. And they are installed in a housing with BMS. I dunno what that weight limit is but it may be doable without breaking laws?

Exception perhaps for the “defective” part if that’s the reason it’s being shipped? But they don’t ask about defective or SOC either? I think the main concern is to keep lithium cells off passenger aircraft.

And I dropped off the bike at FedEx facility this morning using shipbikes.com: