What to look for in a battery?

[PsilocyBen17]

What should i look for when purchasing a new battery? I’m looking for 48v 24.5amps. Prices on Alibaba seem to range from $500-$700. What is a mark of quality when looking at batteries?

 

[DieselTech]

What should i look for when purchasing a new battery? I’m looking for 48v 24.5amps. Prices on Alibaba seem to range from $500-$700. What is a mark of quality when looking at batteries?

I would look into Unit Power Pack brand, with LG 4800 or 21700 battery cells.

 

[DieselTech]

I dont know what type/shape battery you are looking for. Or what BMS ratings you need. But both of these batteries have a 40a & 50a continuous discharge rate. They are made with LG 4800 cells.

 

[m@Robertson]

I would look into Unit Power Pack brand, with LG 4800 or 21700 battery cells.

I would give my highest recommendation to NOT go anywhere near Unit Pack Power / a.k.a. UPP. If you hang around the online ebike DIY community long enough you see they have a serious failure rate. They do have customers who sing their praises, but it seems for every ten of those there's another one with a horror story, and over the years that means you see a lot of horror stories. These most commonly take the form of battery packs that are advertised for a certain performance level but whose performance falls off so quickly they can't possibly be using the cells they were advertised to use (there is also the occasional catastrophic failure). For those within warranty, typically the UPP response is to request the pack be sent back - often to the Far East - for testing, then report nothing is wrong with it and send it back. But just as often you hear people say UPP responded to their troubleshooting emails only up to a point and then ghosted them.

Myself, I had a pack that I spec'd out to have a very strong (90a continuous) BMS, with Samsung 25R cells - at the time they were the best, most-capable high output cells available. I wanted a 20ah capacity. I got all of that, but the pack wore out ridiculously fast. Since I had many other 25R packs I knew that wasn't supposed to happen. I went back to the battery seller about it and only then I learned she was using UPP to build her packs for her company. If I had known it up front I would have never touched them.

The most important thing to look for in a battery is the reputation of the seller. That means you write off AliExpress, AliBaba, Amazon and Ebay. You most certainly never do business with a company that ships internationally to you, and is impossible to hold accountable for their product's reliability/quality. That means you are going to pay what a real battery costs but on the plus side its not a bargain that is potentially a failure or a bomb.

You get online on many groups and you participate... and lurk and watch what happens to other people. Let some other pioneer take the arrows in the back and learn from their mistakes. Never do business with anyone who doesn't have a sterling reputation in the community.

Me, my battery supplier is Bicycle Motorworks, who is based in the USA. They only build a battery when someone orders one. That even goes for the off-the-shelf packs. They have done multiple custom packs for me and I have quite a few of their off-the-shelf packs. But its my understanding they are no longer doing custom packs.

 

[ElHegpah]

Agree with Spock's statements completely, they agree with all I have read about this outfit.

Which is not THAT MUCH worse than most of the sellers you will encounter, other than a select few.

Haven't looked into em3ev in a long time, but Paul has always been top-notch.

 

[m@Robertson]

If I was going to buy from a Far East vendor, EM3EV is the only one on my list.

 

[Hoggdoc]

I would give my highest recommendation to NOT go anywhere near Unit Pack Power / a.k.a. UPP. If you hang around the online ebike DIY community long enough you see they have a serious failure rate. They do have customers who sing their praises, but it seems for every ten of those there's another one with a horror story, and over the years that means you see a lot of horror stories. These most commonly take the form of battery packs that are advertised for a certain performance level but whose performance falls off so quickly they can't possibly be using the cells they were advertised to use (there is also the occasional catastrophic failure). For those within warranty, typically the UPP response is to request the pack be sent back - often to the Far East - for testing, then report nothing is wrong with it and send it back. But just as often you hear people say UPP responded to their troubleshooting emails only up to a point and then ghosted them.

Myself, I had a pack that I spec'd out to have a very strong (90a continuous) BMS, with Samsung 25R cells - at the time they were the best, most-capable high output cells available. I wanted a 20ah capacity. I got all of that, but the pack wore out ridiculously fast. Since I had many other 25R packs I knew that wasn't supposed to happen. I went back to the battery seller about it and only then I learned she was using UPP to build her packs for her company. If I had known it up front I would have never touched them.

The most important thing to look for in a battery is the reputation of the seller. That means you write off AliExpress, AliBaba, Amazon and Ebay. You most certainly never do business with a company that ships internationally to you, and is impossible to hold accountable for their product's reliability/quality. That means you are going to pay what a real battery costs but on the plus side its not a bargain that is potentially a failure or a bomb.

You get online on many groups and you participate... and lurk and watch what happens to other people. Let some other pioneer take the arrows in the back and learn from their mistakes. Never do business with anyone who doesn't have a sterling reputation in the community.

Me, my battery supplier is Bicycle Motorworks, who is based in the USA. They only build a battery when someone orders one. That even goes for the off-the-shelf packs. They have done multiple custom packs for me and I have quite a few of their off-the-shelf packs. But its my understanding they are no longer doing custom packs.

Excellent information for anyone looking to replace or buy a new battery pack.