2018 RadPower Battery Alternative

[AHicks]

Which begs 2 questions if you don't mind Mark.

Of the 6 types, do they all pose the same risk for fire, or are some better than others?

When that 18650 LiOn term/spec is used, could that be any one of the 6, or is that term specific to one type?

Sorry, I sucked in Chemistry..... -Al

 

[MarkF]

I'm not up on the chemistry of all the types but here is a little info on them. https://en.wikipedia.org/wiki/Lithium-ion_battery
Yes you can use different types of lithium in 18650 but most are made of Li-cobalt oxide. . What makes the 18650 different is the metal case they are in. This makes them more robust against damage from heavy vibrations and strong bumps. The others come in a thin foil pouch so they work better in different environments like in RC vehicles or airplanes.

 

[tomjasz]

FWIW Typically when builders refer to LiPo they're referring to the hobby packs that are used by drones and RC folks. A pack that can easily become unstable and best left to the RC world, IMNSHO.

 

[Rjbur]

Sure, there are a LOT of options here - assuming you don't need to use the factory RAD rack. If you're looking for options there, for batteries that can be used with that rack, I'm thinking you're pretty limited for compatible choices. I have not looked into that.

If you are not fixed on using the RAD rack, you have a TON of choices. Just remember that rack is not welded to the frame. It could be easily swapped to something that will handle the battery you're interested in. The other thing to remember is that there are only 2 wires coming out of that rack. As long as you don't get them backwards you're good to go!

Myself, I'm considering going to 52 volts as I know the rest of my system will handle it. Would also like to go with the LiFe battery chemistry (vs. LiPo) as I feel better from a safety perspective. The rest of the bike has been done my way. If I could get a fair offer for the Rad battery I could justify finishing it up my way. Otherwise, there's nothing wrong with this battery, I'll just continue using it. -Al

I believe you will also have to consider the "controller" as well...

I believe that's what they call that black box the batter attaches to.

It has a limit as to how much power you can pump though it and I don't know if you can simply change from the 48V battery to a 52V using the same controller??

 

[JRA]

FWIW Typically when builders refer to LiPo they're referring to the hobby packs that are used by drones and RC folks. A pack that can easily become unstable and best left to the RC world, IMNSHO.

This defines the point I was after nicely.

Also the BMS typical of 18650 Li batteries manages the cells so that they can’t vary in amperage enough to cause safety issues. In general LiPo hobby type batteries forgo this and so charging/discharging management is much more finicky and way less safe overall.

 

[tomjasz]

This defines the point I was after nicely.

Also the BMS typical of 18650 Li batteries manages the cells so that they can’t vary in amperage enough to cause safety issues. In general LiPo hobby type batteries forgo this and so charging/discharging management is much more finicky and way less safe overall.

LiPo, hobby batts are also used with a BMS by many. Since any overcharge or discharge can cause puffing and fire. Very unstable compared to the right choice in18650's

 

[JRA]

LiPo, hobby batts are also used with a BMS by many. Since any overcharge or discharge can cause puffing and fire. Very unstable compared to the right choice in18650's

I haven't ever used them personally but the setups I have seen on ES over the years seem to lack a BMS but I am sure you are right.....

 

[tomjasz]

I haven't ever used them personally but the setups I have seen on ES over the years seem to lack a BMS but I am sure you are right.....

Of course, you are correct, it sure seems like that! Folks like Dnmun had quite a following and there's a bunch of threads on Lipo BMS. I have ALL the gear to manage Lipo, but one puffy pack and the exacting guidelines sent me running. I have several welders at will run on small Lipo packs but I stay with my big 12V marine recycled battery. MUCH safer in a basement shop. As it is I keep my dozen batteries in a double walled steel fire cabinet with smoke and heat sensors.

 

[AHicks]

I believe you will also have to consider the "controller" as well...

I believe that's what they call that black box the batter attaches to.

It has a limit as to how much power you can pump though it and I don't know if you can simply change from the 48V battery to a 52V using the same controller??

Please realize that though the bike I have started out as a production bike, that's no longer the case. It's been modified. The entire electrical system has been replaced with a "kit" and I've done a LOT of research determining what it can/can't do.

You do make a good point regarding the need to do your homework prior to making modifications, no matter how small they may seem, on anything electrical on an e-bike.

That said, many 48v systems will handle 52v. There's a lot to it though, and you should do your homework to know what to expect.

 

[tomjasz]

There are some excellent controllers that will run 24,36,48&52v batts.
EM3ev and Grin are my two go to resellers.

 

[Alex M]

When that 18650 LiOn term/spec is used, could that be any one of the 6, or is that term specific to one type?

Seems a typo here, should read Li-Ion.

Regardless of lingo that hobbyists are using - which doesn't always make sense - there is a distinction on sellers/suppliers websites where some batteries are called just "Li-Ion" and some - LiFePO4: (Link Removed - No Longer Exists)

I vaguely recall that LiFePO4 are more fire-resistant than other common Li-types.

On top of that, there are design quality features like metal foil around individual cells etc, it can be found on cells of either chemistry type, and this is something that battery pack suppliers (and Ebike sellers) don't always disclose.

Regarding (old) OP question about generic batts for RAD - I don't see serious issues as long as you can find and replace the battery tray, and Chinese after-market suppliers so far have been good at it.

 

[AHicks]

You're right on the LiOn, that was a typo, now corrected to minimize making this any more confusing than it is! -Al

 

[Alex M]

My only purpose was to make things clear-er ...

For the sake of clarity, again - LiFePO4 that I mentioned in the previous post, correspond to #4 on the list by MarkF: "Li - Iron phosphate". Fe (or Ferrum) is the chemical term for iron. Note that "PO" in LiFePO4 has nothing to do with "PO" in the abbreviation LIPO (Li-Polymer) - this is just unfortunate coincidence. The former PO means "Phosphate", i.e. chemical element, while the latter PO - "polymer", i.e. how molecules are tied together.

I don't think that all 6 batteries on the list are Li-ion or LIPO (aka Li-polymer). This is not what articles are telling me, and suppliers also differentiate Li-ion from Li-polymer. It has been my understanding that LiFePO4 (often called LiFe or Lifers) belong to neither Li-ion nor Li-polymer. LiFePO4 have better fire resistance than LIPO or Li-ion, they burn less efficiently.

 

[AHicks]

AND, LiFe are 3.3v, not 3.6v, making the need for caution fairly urgent. If you try charging an LiFe at 3.6v, you're going to have issues.....

 

[Alex M]

Always, always keep correct charging voltage for your particular battery. Read fine print in the manual or do your own research if necessary.