36v vs 48v batteries

[Nick R.]

I'm getting ready to buy a BBSO2 mid-drive from Luna for my recumbent trike and am totally confused as to which battery to order. I have read somewhere that after a 36v battery uses 1/2 of it's charge it loses power, and that does not happen with 48v batteries. The only thing I know about DC power and batteries is the hot wire is red and the black is ground, however I do have good mechanical skills and since my bad back will not allow me to walk I could maybe extend my ride in style. Any help to an old vet would be appreciated. By the way cost is definitely a concern, Thanks

 

[Jon NCal]

Luna only sell 48v BBS02 version, so 36v battery is not compatible.

 

[Hangdog]

You can run any 48v motor with a 36v battery...48v battery will spin the motor faster but with less range for a comparable size cell count.torque will remain the same up to max watts for either battery.that is my understanding.check on grin technologies website for a more thorough tutorial.

 

[Sunder]

Running a 36v battery on a 48v system will not work. The low voltage cutoff will shut everything down, even if the battery still has power in it.

It's also absolute crap about 36V batteries losing power at 1/2 charge. All a 48v battery is, is a 36v battery with 33% extra cells. If a battery type loses the ability to maintain current delivery at half charge (and some really cheap types do), then it will exhibit exactly the same behaviour at 48v. So unless someone was comparing a cheap 36v with a good quality 48v, I call shenanigans.

The final thing I will mention is that on mid-drive systems, if you intend to pedal at all, you really need to match the voltage with the system. Amateur cyclists maintain a cadence (how fast they pedal) of 60-80rpm. Pro cyclists are 90-120 rpm. So if you bought a 36v system designed to go 80rpm, and put a 48v battery in there, it really is designed to go 106rpm, which the average cyclist would have a hard time making any significant contribution, or alternatively, you change the gearing so you can keep up, and the system is no longer efficient and can overheat.

If you have no intention of pedalling, the last paragraph doesn't matter at all.

 

[flat tire]

A very long story short, more voltage is better. Especially at double digit levels.

 

[999zip999]

Get a 13s or 48volt battery or better a 14s 52volt battery. Both would work. Get the best cells you can. Not cells that just might work. Meaning cells that make up the battery pack are so cheap they can barely make it work and wear out prematurely. Lots of junk batteries out there ask before you buy. Save money.

 

[Nick R.]

Thanks to all that replied I'm very grateful for your help. these are the two batteries that I was looking at and need help to decide, I'm wondering if the Dolphin is too big for the BBSO2 motor. #1-Ultra slim 48v 12ah Panasonic NCR 18650PF 3 cell Lithium-ion W/charger for $420, #2- Dolphin 52v 12ah Panasonic NCR 18650 PF 3 cell Lithium-ion W/charger for $455. There is only $35 difference which I consider small for such a huge upgrade. These prices were stated on Bafang USA.

 

[Nick R.]

Hi there. The PF is a fair cell. It's not bad, but it isn't great, so you might consider choosing better cells. If you plan to use your bike extensively, you might consider purchasing a quality battery made with cells suited to ebike use. You can find equivalent quality from a well-reviewed vendor which supplies packs to Luna- "Unit Pack Power".

If you don't mind a little extra weight you can gain a fair bit of versatility, easier installation and lower maintenance with a hub motor.

The higher voltage setup will give you more speed. A 36V system will work but 48V is a much better experience if you're over 140 lbs. If you enjoy pedaling or don't need much power, 36V is quite adequate.

Keep in mind that the "52V" battery you see at Luna Cycle is more accurately a "50V" battery, so if you search for that you will find some more reputable and reliable options.

Hi eTrike, I need serious help! I'm an 89yr old wounded vet of WWII and find it very painful to walk, Had triple bypass last year and the Dr. gave me an ultimatum, exercise or die, so I bought an American made trike (Catrike Expedition) for exercise. I try to pedal 3 t0 4 mi every other day, I have had a 14mi round trip but came home completely tuckered out, also when I have a head wind it pushes me to the limit of my strength. I do have common sense and good mechanical ability but very very dumb with things DC electric and bicycles. I looked at the hub motors and tried to compare them with mid drives, It seemed to me that the mid drive had more options and the installation was no problem also the Bionx was more costly. Since I have no DC electric and bicycle knowledge I need lots of serious UNBIASED opinions so I turn to this forum and people like you for a fair appraisal on what systems are better for someone like myself. Thank you for your interest and any help, God bless you for your kindness. Nick R.

 

[999zip999]

Where are you located ?

 

[Nick R.]

Where are you located ?

Hi 999, I live in Ellenton Fl. The suburb of Bradenton Fl. that is just south of Tampa Bay Nick R.

 

[ndavidow]

To get the energy the battery can hold, multiply the charge (number of amp hours) times the voltage (this gives watt hours).

A 36V battery will store 25% less energy than the same Ah 48V battery, because it has 25% less voltage. So, the 36V battery will theoretically have 25% less range, or three quarters the range of the 48V.

The lower voltage also affects the top speed of the motor, and the speed of the motor relates to efficiency, to that can have an affect on range too, but calculating it is not so straight forward.

 

[999zip999]

But when using 48v you may have a tendency to use more energy off the start to get that Thrill of the wind in your hair. The 36v goes slower and stops the high demand sooner at a lower speed. So more waste with higher voltage but with a bigger smile. Me at 72v 7,000 watts smiles go to fear in a good way. Like a roller coaster. I like 52v 14s 18650 for now the higher the quality the less stress the longer they may last. Meaning don't touch the black and red wires together. User error.

 

[Nick R.]

But when using 48v you may have a tendency to use more energy off the start to get that Thrill of the wind in your hair. The 36v goes slower and stops the high demand sooner at a lower speed. So more waste with higher voltage but with a bigger smile. Me at 72v 7,000 watts smiles go to fear in a good way. Like a roller coaster. I like 52v 14s 18650 for now the higher the quality the less stress the longer they may last. Meaning don't touch the black and red wires together. User error.

OH MY GOSH,LOL LOL what make that last paragraph even funnier is that is about the sum total of my DC knowledge, isn't that scary. Nick R.