Best 18650 battery for the buck? Best deals?

[Wheazel]

Phase 1: Recommended Ultrafire-esque cells
Phase 2: Vigorously defend decision to recommend Ultrafire-esque cells
Phase 3: ?
Phase 4 Profit!

:lol:

 

[Overclocker]

[

these came out to about $1 per cell. got them via amazon. genuine 3M portable projector batteries. chinese 18650 from a company i've never heard of, Amperex. i guess 3M wouldn't risk their reputation on explosive cells. haven't heard of any recalls

and they come welded w/ nickel tabs so a noob could easily wire them up

They made a mediocre pack on the cheap, but their age will affect their service. They weren't reject cells, the product was discontinued. A market failure.

i think it was your post on ESFB that prompted me to buy these cells was in california at that time so i went ahead

 

[Overclocker]

i'm sure i got graphs of this cell somewhere, which isn't very pretty (IR is a bit high)

now take your condescending tone and gtfo

What is the capacity and IR of those cells?

2100mah. runs cool at 3A continuous. a bit warm at 4A. definitely not a top performer but at $1 you can't complain. i'll be running them in parallel w/ some better cells

 

[msebold]

Panasonic NCR18650BE is the best value in my opinion. Great price per watt hour, good balance between high drain and high capacity (10A max current).

Thanks. I'm trying to compile a list of 18650 cells that are the best to use in my battery pack. When I spot a good deal on bulk cells I'll know which ones to try to jump on. NCR18650 GA and PF cells are now on my list. The BE cells look good too at 2900mah, but I am as of yet unable to find anyone selling these in bulk. I'll keep looking.

Overall weight is a consideration, so I don't think I want to go with cells that produce less than 2500mah. Continuous amps will probably not be an issue as my motor draws 60amps max and any pack I make will probably be at least 8p. I think that any of these cells will produce 60 amps continuous in an 8p configuration.

Thanks again for your input on the BE cells.

 

[msebold]

I can only say so far so good, but I haven't had them long. The price has gone up since I got mine for 4x $7.99, it's $9.75 for the set now. 15 ratings on Amazon, 10 at 5, 4 at 4 and a 3. The down votes are just about their device problems, actually.

https://www.amazon.com/gp/product/B01CNV27K4/ref=od_aui_detailpages00?ie=UTF8&psc=1

Looks too good to be true. 5800mah and 1800 recharges? I notice that the amazon ad does not specify what type of lithium cells these are other than "Perman." So what's your experience? Are you getting anywhere near 5800mah on these cells? Can complain about the price, but performance claims seem dubious.

 

[msebold]

Is this a joke?

Not unless you know a good punchline.

 

[msebold]

Buy used tesla cells. it is the cheapest way to get QUALITY 18650BE's

Buy from someone who has sold a fair amount so you have a good idea you are getting what they are saying you are getting.

If you are making your own pack I recommend not to solder them, and if you are going to solder them get a HIGH powered iron so you can do it quick. You don't want to heat the "jelly roll" up too much. If you use a low powered soldering iron, all you will do is heat up the whole cell. You need to hit it fast and hot to get the solder to melt and get a good bond.

Welding is the right way..

Eric

Thanks Eric. I plan to get a battery spot welder. I am interested in the used Tesla 18650 BE cells. Why would you want to buy used cells? If they're being removed from use in a Tesla vehicle doesn't that mean they are near the end of their useful life? Why do you find these to be a good buy?

 

[parabellum]

Why would you want to buy used cells? If they're being removed from use in a Tesla vehicle doesn't that mean they are near the end of their useful life? Why do you find these to be a good buy?

Those are usually removed from wrecked vehicles. Many of them have under 100 cycles in conservative DOD region and good for thousands more. Responsible seller will know how many cycles those had and will check and share IR and capacity average before you buy. Then, if those cells sneaked in to a Tesla, you can be sure they are A+ grade. :wink:

 

[msebold]

Why would you want to buy used cells? If they're being removed from use in a Tesla vehicle doesn't that mean they are near the end of their useful life? Why do you find these to be a good buy?

Those are usually removed from wrecked vehicles. Many of them have under 100 cycles in conservative DOD region and good for thousands more. Responsible seller will know how many cycles those had and will check and share IR and capacity average before you buy. Then, if those cells sneaked in to a Tesla, you can be sure they are A+ grade. :wink:

Thanks! Got a link, or know a place where I might keep an eye out for these?

 

[parabellum]

Thanks! Got a link, or know a place where I might keep an eye out for these?

https://endless-sphere.com/forums/viewtopic.php?f=9&t=67661

 

[Lurkin]

The reality is, there is no 'best cell' or 'best cell for the buck' until you qualify what it is you are using it for.

Parameters include cost, safety, knowledge, user friendliness, personal preference, size/shape, quality, DIY/vendor assembled, required discharge rate, capacity, compatibility, longevity expectations to name a few...

Lots of variable here. As you know, I am inquiring about cost versus output of individual cells. You know of any particular 18650 cells that have safety issues, that are not user friendly, that vary in size or shape, or that require assembly? Not really sure what you're trying to relate here Lurkin.

The decision you are trying to make is more complex than comparing cost to output. Choose your components (hub/middrive, controller and thus output wattage required) and work backwards, the cells capacity and discharge requirements should be the last step in the planning process.

Ergo, the decision is based on what you need, not whats available.

For instance, buy low capacity, high discharge cells then discharge them slowly - whats the point paying for high discharge cells?
wattage required > packs ability to discharge - are you going to roast the pack?
Living at a farm with a paddock for charging and storing cells - why use 18650s? why not consider lipo?
limited space on the bike for a battery - indicates high capacity cells.. but what discharge rate is required per cell?
do you have the ability to assemble a 18650 pack safely?
do you have the knowledge to charge and deal with lipo?
does the battery have the capacity loss characteristics which are acceptable to you?

None of these decisions have discussed price at all. Its almost irrelevant right up until you nail down what battery actually suits your needs - chemistry, discharge rate, capacity, size, pack assembly..... I think you'll find if you do a thorough job of cell choice, it will limit the cells acceptable to you and then its just a matter of finding them cheaply.

 

[wineboyrider]

@lurkin: Good logical advice. I use HK multistar lipo and love them for the price and my application at this point. I paid $350 for 1400 wh of 2.5 C discharge capability and so far with only a 2c capacity and price the batteries are an excellent value.

 

[Killer-B]

Just thought Id pop in and say Hi. Ive built many of my own 18650 pack. Latest is 24s 6p.. id be happy to help others in my area.Ive got a good cell hookup and the welder Guelph Ontario Canada

 

[Dauntless]

So the entrance of the park was completely black in my camera without the maybe 5w light.

So what's your experience? . . . .performance claims seem dubious.

Only with seeing batteries actually WORK. Nothing important like generating numbers when they're out of use, just frivolously seeing them thru satisfactorially in the real world. Obviously the Wizard of Oz would never approve.

Not too familiar with batteries living up to claims. But I've worked with video all my life, they never run the camera or light as long as they say they will. I'd guess 1ah would run the flashlight less than an hour.

For the moment I'm running around getting some test shots to see how much good these little flashlights might do me. When it overpowers the greenyellow light in the parking garage, that's impressive. I'm used to dragging around a car battery on a cart to run a couple of 100w quartz lights that don't perform like that. LED is putting out as much as 10 times what quartz does for the same wattage, beating CFL's almost as well with much better light. Not are these things bright, they're white light. The quartz are red. The existing light you find in the real world is mostly yellow these days, that's the worst color. Cops complain they can't read license plates under the streetlights. You know the restaurant light where you can't read the menu? Green technology, doesn't use much more electricity than complete darkness, nor can you see much better.

View attachment 1

I could post these pictures in the right forum and just a little discussion would really get them to unleash the questions. How long does it take for the voltage to drop and cause the color of the light to change? I haven't seen it change, the batteries are giving consistent voltage. (On regular AC a 1 volt drop gives a 10 degree change in color temperature, just a few volts can show a difference.)

I've been doing this for hours seeing just how much impact one little $2.92 flashlight has, with a $2 rechargeable battery. It's a focus spot/flood. Those expensive "Tactical Flashlights" you see on the commercials are 4 or more cells, I hear they heat up quickly and burn your hand suddenly. I have 1-2 cells and they don't seem to get so hot.

They may not be the highest rated batteries, but they can't be junk or they'd already be dead. And that's just KILLING my stalker on this thread. (Note HOW MANY times he responds to one post.) But darn, they just won't burn up for him.

 

[msebold]

The decision you are trying to make is more complex than comparing cost to output. Choose your components (hub/middrive, controller and thus output wattage required) and work backwards, the cells capacity and discharge requirements should be the last step in the planning process.

Ergo, the decision is based on what you need, not whats available.

For instance, buy low capacity, high discharge cells then discharge them slowly - whats the point paying for high discharge cells?
wattage required > packs ability to discharge - are you going to roast the pack?
Living at a farm with a paddock for charging and storing cells - why use 18650s? why not consider lipo?
limited space on the bike for a battery - indicates high capacity cells.. but what discharge rate is required per cell?
do you have the ability to assemble a 18650 pack safely?
do you have the knowledge to charge and deal with lipo?
does the battery have the capacity loss characteristics which are acceptable to you?

None of these decisions have discussed price at all. Its almost irrelevant right up until you nail down what battery actually suits your needs - chemistry, discharge rate, capacity, size, pack assembly..... I think you'll find if you do a thorough job of cell choice, it will limit the cells acceptable to you and then its just a matter of finding them cheaply.

Thank you for your advice. However, as I mentioned once or twice in this thread, I have already purchased my motor, a 60 amp, 3000 watt, direct drive motor. This system requires high output batteries.

Ergo, I have already settled on high-output 18650 cells (unless I find something even better).

Thanks again for all the wonderful advice on motor and drive selection, but again, all I was really asking was for suggestions on the best bang for the buck in a high-output 18650 cell. Not that complicated an issue.

 

[msebold]

So the entrance of the park was completely black in my camera without the maybe 5w light.

Thanks Dauntless. Perhaps these batteries are worth checking out to power my headlight system. However, I don't think they are what I am looking for to power my 3000 watt DD motor.

Regards.

 

[msebold]

Just thought Id pop in and say Hi. Ive built many of my own 18650 pack. Latest is 24s 6p.. id be happy to help others in my area.Ive got a good cell hookup and the welder Guelph Ontario Canada

Thanks Killer-B. If you don't mind I might send you a message as I begin to put this battery pack together. I'm sure I could benefit from your experience.

 

[eric1565]

Thanks Eric. I plan to get a battery spot welder. I am interested in the used Tesla 18650 BE cells. Why would you want to buy used cells? If they're being removed from use in a Tesla vehicle doesn't that mean they are near the end of their useful life? Why do you find these to be a good buy?

I say used tesla because the cells get QC'd.

Stay away from Alibaba no idea what u are buying. U rely on the word of a company half way around the world.

I have bought many lipos from hk and never had an issue (as in unexpected fire). All my lipos are expanded. Many have failed over time. I have had fires by shorting and hitting with axe (cells were bad and i was scrwing around) had a 3 cell pack turn into a 2 cell pack while charging and it got pretty warm. Hit with axe and it caught fire.

I have shorted charged Tesla cells and they can go pop but no fire. Much safer than lipo

I have a number of 4s7p tesla packs and they are great. I can burst 21 amps per cell(same as tesla) and they get slightly warm. I can pull 10 amps continuous no problem.

I have an altrax speed controller set to 150 amps on my mini electric motorcycle.

My 2 cents.

 

[msebold]

I have a number of 4s7p tesla packs and they are great. I can burst 21 amps per cell(same as tesla) and they get slightly warm. I can pull 10 amps continuous no problem.

Eric, I'm very interested in the Tesla packs. Any way you might tell me where I might get some of these?

Thx.

 

[swbluto]

I don't expect it to be the 5.8. I don't really have a way to run a capacity test. Lasts for hours in the flashlights, they might be 5-7w.

You seriously don't have a cheap little voltmeter?

It's pretty simple measuring the capacity. (energy)capacity = INTEGRAL( v(t)*i(t),dt) [(amphour)capacity = INTEGRAL(i(t),dt)]

A simple Riemann sum is good enough, IMO. Don't really need to come up with a polynomial approximating curve for the v(t),I(t) curves. (For the less mathematically trained, you just sum up the voltage*current*time_step values over time, with measurements every 1-60 minutes(The time step); more frequent measurements makes for more accuracy)

Now, if you're saying you lack a suitable load (Power resistors, bulb, nichrome wire, etc.) and a couple of alligator clips, I feel for you.

Those 200w 10ohm variable resistors you can get from China via ebay for $30 are awfully nice for this kind of thing.

If only I had a functioning lab power supply (For charging), I might offer to do some free testing for the community.

 

[eric1565]

Eric, I'm very interested in the Tesla packs. Any way you might tell me where I might get some of these?

I made the packs myself. I used a welder made by riba. I bought the cells from okashira.

 

[msebold]

I made the packs myself. I used a welder made by riba. I bought the cells from okashira.

I'm sorry. I'm trying to make sure I understand what Okashira sells (if he still sells them). Did you receive the individual 18650 Tesla cells, or did you receive Tesla modules (or partial modules) that you were working with?

 

[cal3thousand]

I made the packs myself. I used a welder made by riba. I bought the cells from okashira.

I'm sorry. I'm trying to make sure I understand what Okashira sells (if he still sells them). Did you receive the individual 18650 Tesla cells, or did you receive Tesla modules (or partial modules) that you were working with?

He sells them all! He gets full modules and will sell partials, loose cells and built packs

 

[parabellum]

He gets full modules

Sometimes even cars.

 

[okashira]

Yep, I currently have
-4 Model S Drive units
-around 2,500 cells
-2 module
-millions of contactors, relays, precharge resistors, connectors
-5 A123 LiFePO4 modules (Got another Spark EV)
-etc etc...