My experience with Sun-thing28

Background on me -- Been a member for several years. I have two ebikes. I used 2 ping batteries until they both finally died. I fixed each multiple times, getting replacement cell groups from Ping and hacking up the packs and reassembling. When I had had enough of that, I bought a 48V 20AH LiFePO4 battery on ebay from Sun-thing28. The vendor has been mentioned more frequently on the forums as a cheap Ping.

The battery got to me exactly on stated schedule. The problem was the battery never charged. It would get to 50V before the charger shut off. Charger voltage was 60V. The pack wouldn't balance. I tried about 30 different kind of discharge cycles to make it balance, but it wouldn't. Sun-thing told me to replace the BMS so I did. It didn't help. More discharging, more charging, more measuring... The cells are much harder to access than a ping pack. He puts tape all over everything and the cell tabs were crimped. I had to work quickly for the ebay buyer protection so I didn't have a lot of time to take pics but I spent hours trying to fix the pack. He offered me $50 to keep it, but of course I didn't accept that. That would have worked out to $400 for a busted battery. He admitted it wasn't working like it was supposed to but he really didn't want me to return it. Ultimately I had to. The cheapest shipping I could find was $165. Sun-thing was adamant that he wouldn't reimburse any of the return costs. After I gave him the tracking number he hasn't responded to any emails. I still haven't gotten the refund from ebay, but I expect when the dust clears I'll get the original costs back but will lose $165 on net and lots of hours from the whole thing. Just to be clear, the pack never got above 50V.

Here's his info:

Sun ShaoWen
Room 301. Building 2. Shenzhen Bolun School Practice Base
Zhuguang Road,Xili Town,Nanshan
ShenZhen 广东省 518054
China

I see his name recommended a lot, but from everything I have seen it's junk. I guess problems get talked about a lot more than success stories, but I certainly wouldn't go there. I only had to see inside one to make that decision.

nope, they are not junk.

a buncha guys have bot the battery from him and have had no problems.

i have seen how they are built and i have seen pictures of the BMS and it looks robust.

i have no idea how this guy could have so many problems and he never ever posted any of this to the sphere before so we could help him. that would have been more appropriate and we coulda made his battery work for him.

his comment about how it would only charge to 50V was very telling since he said the charger output 60V. if he had actually asked for help then we could have identified what he could do to balance the battery.

he wanted to send it back without the ok from the receiver. so he has a problem. wasted even more money imo.

there is nothing wrong with the manufacture or design of these packs. we could have got him fixed up in a day.

Hi Dnmun. Thanks in large part to help you have given me in the past (and I thank you for that) I know my way around a battery pack. Your implication is that I should be happy to do surgery on a brand new item (which I actually did do) and spend more time taking pictures, typing measurements, and consulting with the forum (okay fine, I didn't do that because of how highly I value my time). I appreciate that the amazing resource that endless-sphere is here, I actually do, but I did decide that I shouldn't have to fix a brand new item. And to be fair to me, dnmun, I'm never said I expected sun-thing to fully reimburse me. I just don't think his response was professional and it's important that people, especially the noobs that frequently get pointed in sun-thing's direction, know that at best it might not be plug and play, and at worse you get screwed. I think the vets know full well that that's the price to pay for cheap Chinese goods, but yes, I do think it's worth reiterating.

i saw no evidence the pack had to be cut apart. it appears that it was never balanced since you said it would only charge to 50V.

if you had asked for advice when you had the battery present we could have shown you how to force it into balance so it would fully charge.

none of that happened.

Neezy, relatively new ebiker but thanks for the heads up. Totally agree with you that your product should have been plug and play, not a hobbyist nightmare. Looks like Sun-thing28 is a good vendor to avoid for my second project to go along with Dillenger who provided a functionally inadequate system for the initial hub drive.

balancing a battery is not a nightmare. you just have to plug it into the charger and let it charge until it balances.

it has to be done on every battery you buy.

I purchased a kit in order to gain knowledge about ebikes and determine my interest in pursuing more sophisticated systems. The instructions didn't say anything about the battery needing to be balanced, just charge it with the supplied unit until the indicator showed that it was ready for use. I'm sure that you will want the last word, but I'm still avoiding Sun-thing28 for all future endeavors thanks to this thread, .

I've got two Sunthing 48V 10Ahr packs connected in parallel on a recumbent. They've got maybe 30 cycles on them and the balance has gradually improved. When I first got them they were only able to get to 56.5 volts. As of yesterday, with some fairly long not-in-use balance periods they are able to get to 59.5. It just takes a really long time for them to perk up and balance. Having said that, I do not believe the cells are as high quality as my Pings. For example, with about 4 Ahr drawn on the packs, out of 20Ahr, they are around 51.5V, with pretty deep sag to maybe 48.5V on watt spikes of maybe 700 watts. Having also used several Ping packs (although those are 15Ahr) also 2 in parallel, they feel inferior in their zippiness comparatively, although that could be just my imagination, for 20Ahr vs 30Ahr configs. I charge them both at once through a Y cable, and each has its own BMS. I hope they hold up.

what is really so sad about this is how easy it would have been to make his battery work for him and he never ever said a thing here about it until he started this thread to trash the seller. i have never seen a battery maker ever take a battery back so now this guy has lost a perfectly useful battery and wasted hundreds of dollars and time for no reason.

all this time we spend helping people out is just a waste in this case. really really sad.

Dnmun, your assumptions are spectacular. Naturally, extended time left on the charger was my first approach, of many, including various discharge cycles. This is not my first battery. I've been nursing LiFePo4 packs for years and years.

Neezy, thanks again; I'm on this site to learn, try to contribute where possible, but not get involved in petty arguments. The other thing gleaned from your post is who to block from now on.

this is not a petty argument. my point is that he never mentioned that the battery had problems here when he had it and we could offer advice to make it work.

but when he decided it was the fault of the sun-thing28 guy then he posted up this thread trashing him.

people have done this to ping too. the only other person i saw send a battery back which was to ping made the claim that ping had sold him a defective battery and that he took it apart to prove it had been previously used and sold to him. but the guy had actually pulled the sense wire loose from the terminal himself when he took the battery apart.

so now without proving the battery was defective, this sellers reputation has been trashed and this other guy has come on here to exclaim how cheap chinese junk is all bad, and he will never buy ... same old, same old..

this is not petty because the google bot will post all this crap for everybody to see, and i think the guy knows that. i feel it is how people try to force sellers to come to their terms by threatening them that way.

i do not feel it is fair to the seller either since he did not receive a chance to make a public reply, so i have to stand in for the seller instead and because i do know more about the battery than most here do.

Dnmun, what would you have advised, beyond what I've already described trying. I'm trying to be fair and open minded and respect your opinion. Thanks

i feel that you should have posted up the problem you were having with the battery. when it arrived and you felt it was not charging up properly. this is stuff we deal with every day.

most of the time people will post up asking for help and then just never reply to requests we make to evaluate the condition and performance of the battery. this could also be a problem because so many people here with no clue about how a BMS functions would be offering inaccurate and wasteful advice or just the usual "cheap chinese junk. never buy it.. buy american" jingoism. all batteries are made in china. all of them.

i suspect most of these people are just not used to having others ask them questions that requires them to do testing or examinations they don't understand or they just do not wanna participate in a conversation they fear will make them appear to others here on the sphere as inexperienced or not competent as they imagine the insiders with blue letters on their names are.

if you had started a thread about how sun-thing had sent you a battery that did not work, we, myself in particular, would have walked you through each step to take in isolating what caused the battery to not charge up.

if the battery or the BMS had a defect we could have identified it and determined how to fix it.

there are a lot of people here who would also have offered opinions and made many free suggestions that have nothing to do with isolating the problem. that is how people here seem to function.

i also failed to get a reply from sun-thing when i had emailed them asking to get some of their pouches to test. i was annoyed to say the least, but they are a sales organization. sun-thing is a made up name that means something in chinese i am sure, but there is no guy who goes by that name.

in fact it appears they are using a new identity on ebay and not using the sun-thing name when i do an ebay search. so that may be an indication they have had complaints and they are shifting away from using a name that has gained more negatives against them on ebay.

so if you had examined the pack under some supervision and determined that some part was defective then you could make a claim of defective product through paypal and been reimbursed.

by allowing the seller to send you a new BMS then they can say they sent you the needed replacement part you requested so now that you have replaced the BMS, it is not their problem since it was 'modified' by you and not subject to their quality control so they would be out of the loop.

i doubt if the original BMS was defective. i have never seen a defective BMS from the manufacturer. except the 'Smart BMS' from BMS battery with the defective surface mount parts leading to nothing on the pcb.

i have seen pictures of the BMS that sun-thing uses and they did look very much standard issue so i would not expect that to have been the cause of your problem. it could even have been a charger problem. there is just no way to know.

my first guess would be that the pack had become extremely unbalanced from sitting on the shelf for a year waiting for someone to buy it. lifepo4 is very subject to self discharge mechanisms and when the battery has large capacity cells, then it takes forever to restore full charge to the ones that have the high self discharge rates after they have been sitting for a long time.

there is now this other guy who also started a thread trashing sun-thing guy and he also never ever asked for help here and even though he has a thread trashing the seller, he has no interest in examining the battery to determine what is defective or has come back to his own thread to ask for advice or help. so he has also lost use of his battery. eventually someone here will tell him he can use the battery by removing the BMS and he will. then that will be the end of his battery when it gets damaged by over discharging or over charging.

this is all particularly frustrating to me because i have hoped that it would be possible to use this place as a way to show people how to analytically evaluate battery problems but the only thing that people here seem to care about is how fast the ebike goes. that is what determines the 'credibility' of the author. the faster your ebike, the more believable your comments.

even my ZENN car is subject to derision because it does not go fast like a Tesla or drive on the freeway with the gas cars and semitrucks.

this is just the male ego culture fostered here where people feel entitled to threaten you with violence or make racial and sexist slurs without any condemnation but if you don't follow their stupid rules for selling something they will banish you even if you only have one post.

none of this is helpful for those who have problems with their battery. none of it will ever change.

Good commentary.

Just one point though, it seems that Sun-thing28 is still very much an active Ebay ID.

http://www.ebay.com/sch/sun-thing28/m.html?_nkw=&_armrs=1&_ipg=&_from=

In defense to sun-thing I'll describe my experience with my 48v 20ah lifepo4 pack from him. Battery took 3 months to arrive, it was my first big international purchase, waiting was driving me crazy. Not his fault, Brazilian customs are ridiculously slow, the tracking log don't make it clear but I'd say the battery spent at least 40 days in the customs. Battery arrived, I let it on my room for a month, didn't have time to install it. Installed it and first charge was a nightmare, even made a topic about that. Sun-thing fault? Nope, I was stupid enough to not notice that the charger was 220v while I was trying to plug on 110v. First charge was ok, I bought a wattmeter to check capacity some months after that. About 18 but not from cut off voltage, so it's good. Actually the meter doesn't work anymore, but I still get same range. The pack is so wonderfully balanced that after the charger turns off the first time it usually only turn on again once, sometimes it doesn't turn on anymore, perfectly balanced. The pack doesn't get hot, doesn't seems to be running out of capacity, its perfect. Every vendor has problems, some products will have problems, that can be reduced but not avoided. The pack would have been pretty much plug and play for me if I had noticed it was a 220v charger. Besides that, never had a problem and it was a very well spent money.

Lucky you mateusleo. Some people don't have that luck and get ripped off.

can you document that or is just your 'informed' opinion? most if not all of us use chinese manufactured lifepo4 and lipo batteries in spite of your opinion. of course the company you shill for also uses batteries made in china too. but you think your patrons are better.

I think this thread says it all.

You can do a search for "sun thing" and see the other people who got scammed too.

I guess you think its ok to get scammed huh dnum?

The BMS in my sun-thing battery had been repaired before it was sold to me, a lousy repair too.
Status after 50 cycles is: BMS is trash and one cell is dead. I have another BMS and are rebuilding the pack.

Ignore dnmum he is just querulous

/philip

It seems like he changed the way he makes the packs or changed supplier. My battery is the one with silver tape everywhere, I suppose the ones wrapped in blue plastic are not as good as the ones wrapped in silver tape.

Personally, I have nothing bad to say about Sun-Thing28 on eBay. Everything went smoothly, and communication quick (and understandable).

I bought the 48v 15Ah pack from SunThing28 a year ago, and have had no problems what so ever. It has a range (capacity) of 14.4ah with @ a 10amp discharge. ( I didn't wait for the LVC cut-off as I didn't want to push the scooter)

Now my opinion is:

1) We can all get a bad/defective battery...
2) Some batteries are better than others...
3) Some batteries cost TWICE (some THREE times) as much...
4) All batteries are going to die...

In my case, I got a 48v 15Ah LifePo4 (pouch) battery, with a 6 amp charger for $330 usd (shipping included). I have seen some batteries from V-Power (or similar) for @ the same price, but didn't want the 18650 soldered/connection/cell problems.

I also could have bought a Ping battery for @ twice the price, but I am on a limited budget, so that option was out of range.

I could have also bought a "high-end" battery, but that would have cost me @ THREE times as much, so definitely not an option.

So in closing, some people can afford BMW's,. Mercedes, Porches, and some people drive Honda's, Toyota's, and some of us drive Kia's, Hyundai's etc...

Either way, when I ride my "electric scooter" to do local errands, and the warm wind is gliding past my cheeks, I always have a BIG SMILE on my face....

I started riding with SLA's, now I have LifePo4, and maybe one day I'll be riding a hydrogen or nuclear battery.... who knows what's next... lol

Just my 2 cents worth... IAN.

imorton said:

Personally, I have nothing bad to say about Sun-Thing28 on eBay. Everything went smoothly, and communication quick (and understandable).

I bought the 48v 15Ah pack from SunThing28 a year ago, and have had no problems what so ever. It has a range (capacity) of 14.4ah with @ a 10amp discharge. ( I didn't wait for the LVC cut-off as I didn't want to push the scooter)

Now my opinion is:

1) We can all get a bad/defective battery...
2) Some batteries are better than others...
3) Some batteries cost TWICE (some THREE times) as much...
4) All batteries are going to die...

In my case, I got a 48v 15Ah LifePo4 (pouch) battery, with a 6 amp charger for $330 usd (shipping included). I have seen some batteries from V-Power (or similar) for @ the same price, but didn't want the 18650 soldered/connection/cell problems.

I also could have bought a Ping battery for @ twice the price, but I am on a limited budget, so that option was out of range.

I could have also bought a "high-end" battery, but that would have cost me @ THREE times as much, so definitely not an option.

So in closing, some people can afford BMW's,. Mercedes, Porches, and some people drive Honda's, Toyota's, and some of us drive Kia's, Hyundai's etc...

Either way, when I ride my "electric scooter" to do local errands, and the warm wind is gliding past my cheeks, I always have a BIG SMILE on my face....

I started riding with SLA's, now I have LifePo4, and maybe one day I'll be riding a hydrogen or nuclear battery.... who knows what's next... lol

Just my 2 cents worth... IAN.

Click to expand...

I always preferred to drive my ebike rather than the cars. Its fastter in heavy traffic, easy to park (i park anywhere i can lock it up with the padlock haha), saves gast, well, everything that ebikers are tired to know. Also, its kinda cool when people look at you wondering how the frock that guy goes do fast without pedaling... I have my sun-thing for 2 years now, i suppose about 3k kms on it, still fine and same capacity, and i face some high grade hills here.

Going to resurrect this thread, in the interest of efficiency.

Ordered 4/10/2015, received 6/18/2015, more than the 8 week advertised.

Spoiler: I think the battery is fine, and will work. Further testing to come later.

Good communication: They have been contacting me almost daily since I inquired a week ago as to the status of my shipment. The ChinaPost tracking number had no updates, and it arrived in Denver and was stuck in "processing" for a week before it came to my local USPS office. Still, no updates via ChinaPost tracking.

Had to pick the package up at the post office since I was on vacation when they tried to deliver and get my signature. Even the postal clerk laughed at the condition as he retrieved it from the back, it was beat to shit and the battery shifted around inside like a dead body.

Excerpt from the email I sent Sun-Thing28 summarizing condition of item when received:

The styrofoam inside was mostly broken up into tiny pieces, and the usb adapter parts were bouncing around inside loose, as was the battery which shifted position whenever you turned the package side to side. 2 corners of the battery have minor dents in them, but I think it is functional overall. It is currently charging, as it arrived at 50 volts. Please see the pictures to get an idea what shape it was in when it arrived. For future customers, I would highly recommend wrapping the battery itself in soft foam, not rigid foam, and duct taping the foam around it. I have ordered a couple of other batteries and they arrived in perfect condition and were packed with multiple layers of soft flexible foam around them in a quality cardboard box. Your cardboard box was basically flexible and limp, only the tape around it kept it together. See attached photos.


Here are the photos...yeah, apparently China is far away. :? Sorry for the blurry ones, my cell phone must be tired from vacation.

Outside of the package. I think it used to a be a rectangular shaped cardboard box?:





Notice the styrofoam all crumbly and pieces everywhere...



Charger and little usb adapter thingy:



Main damage, hopefully it's just to the outside protective casing: