Reasons not to buy Cheap LiPOs and Alternatives (Don't Buy)

ESK8 Electronics
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Hello All, I made another post on these batteries specifically about the amperage and the risks, but that has been resolved and taken care of. I am making this new thread to discuss if it is a good idea to purchase and use these batteries for a few reasons…

  1. They are technical “used” but they are tested
  2. I have watched THIS video on my batteries and it said that they have high internal resistance which I think means they are dying?
  3. I wanted to use THIS cheapo BMS to bypass it explicitly for charging, but I am worried about the cells becoming unbalanced…
  4. And finally) is 8s1p 8000mah pack with them for a dual 200kv setup a good idea? Batteries

Thanks a million!

Edit: I forgot the link to the BMS :joy: Edit: AND THE BATTERIES

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If they have high internal resistance I would strongly recommend not to get them as they will probably no longer produce the max out put and will run hot. They also may not have many cycles left.

Cheap packs can be bought from HobbyKing with confidence, just don’t get multistar batteries

3

My problem is that I am SERIOUSLY penny pinching, as with buying 8 of those batteries, I am up to 750 USD and I don’t have really any more money to spend… (I haven’t bought them BTW)

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It is cheaper in the long run to buy high quality parts than it is to replace a board that burned down. Lipoly batteries are great, so long as they are meticulously maintained and cared for. They are dangerous otherwise, and as you don’t know how they have been treated, don’t waste your money on them. The battery of an esk8 is NOT the part to skimp on. Doing so will not work out well for you

5

This is defiantly true… So If I were to make a 8-10s pack with about 10-15 mph of range, what sort of Amp Hours would I need and what cells should I use to be budget friendly?

6

for 10s I would recommend 5 8000mah 2S FlightMax’s from HobbyKing. there will be enough room for ground clearance and you will get stacks of range

7

You should definitely buy a pre-built board and not DIY then

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I don’t think that a 700-800 USD Budget should be too unreasonable for a DIY, Right?

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You will spend a significant amount more than you think you will spend, no matter what the amount you think you will spend is.

On a pre-built, the cost is set upfront. This is what you want.

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Not at all. Very reasonable boards can be built with that budget

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I think I have come up with a solution. I am going to purchase some Samsung 25r Cells from BatteryJunction at 3.65 USD for a 10s3p Li-Ion with a total of 7.5 Amp Hours. This will only add about 50 USD to my Budget, bringing it to a solid $800.

Not to shabby for a sensored dual Motor setup? I mean I’m in my mid-teens and I’m a twig so I’m gonna fly :joy: Also I already have 1 VESC I just need a second so that cuts $100

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I have had both good and absolutely terrible experiences with HobbyKing. I have 12s 8000mAh batteries in my single motor board that work fine. I also have the same batteries in my dual motor board and I seemed to be blowing a cell every 2 weeks even though they were 25C cells supposedly capable of 200A.

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I’ve heard it can be hit or miss, so far I’ve only had hits so can’t really complain but I also hear they are pretty good about replacing anything that is DOA.

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Yeah they replace stuff that is DOA, but it sucks to have to wait another 2 weeks twice in a row.

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I received a DOA battery, got it RMAed and received a second DOA battery. So I said screw it and bought a spot welder and a bunch of 18650s and got to work.

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7.5Ah will be plenty I have a 10S at 5Ah or 185Wh and can get 12 miles out of it (also a small person and I don’t floor it the whole time but average something like 15mph occasionally a bit faster if the road is nice) so I think you’ll be fine.

@kuphjr yeah given all the issues I’ve seen people have with their homemade first time spot welding 18650 packs I’m glad I’ve avoided it so far. I’ve just been using lipos for a couple of years, I’ll probably buy a prebuilt 18650 pack in a while here but just dumped a bunch of cash into quadcopter FPV gear for my other favorite hobby :slight_smile:

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I didn’t have issues building my own li-ion pack my first time. I just followed the best practices on this forum. If you ride your board a lot I think it is worth the cost of replacing lipos. After I build another li-ion pack for my single motor board, I am pretty confident in producing packs for other people if you are ever interested.

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Dang, I just checked my soldering iron and it’s only rated to 40w, so I’m not so certain I should use that to do my pack. Does anyone know any cheap solderless kits or tools to make a 18650 pack?

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Seems like NESE pack is pretty decent from the few people I’ve seen use them definitely don’t want to be soldering the cells unless you can keep the heat transfer into the cells to a minimum would definitely go with one of the solder less kits or spot welding and if you plan to diy post a thread for the build to get tips/pointers before calling it good.

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Yea, I do plan on making a thread. I think I’m just gonna do that now.

I actually just went digging in my basement and found a 90-120w soldering gun that was my grandfather’s. I cleaned it up a bit and I have used it fairly recently so I know it is in working order so i guess i can use that. I totally forgot I had it.