[mostly incorrect.. be warned!] - Battery 101

Functional Artist

Active member
Messages
2,599
Reaction score
20
Location
Toledo, Ohio
Battery Basics

FYI:
Battery - is usually used to refer to an individual "battery" cell (like AAA or a 9V)
...but, sometimes a group up of "individual" cells is also referred to as a "battery" (like a 12V car battery)

Battery Module - a group of individual cells connected together make up a "battery module"

Battery Pack - several battery modules, grouped together, are usually referred to as a "battery pack".

In-series- is when (2) or more battery cells/modules are connected together (+) to (-). The positive (+) terminal of a battery cell/module is connected to the negative (-) terminal of another battery cell/module.
(connecting battery cells/modules "in series" will double the voltage but, not the capacity)

In-parallel- is when (2) or more battery cells/modules are connected together (+) to (+) & (-) to (-). The positive (+) terminal of a battery cell/module is connected to the positive (+) terminal of another battery cell/module & the negative (-) terminal of the battery cell/module is also, connected to the negative (-) terminal of the other battery cell/module.
(connecting battery cells/modules "in parallel" will double the capacity but, not the voltage)

Now, lets move on to/with the basics/specifications of Lead (batteries) :thumbsup:

A standard 12V Lead (chemistry) battery (module) is comprised of (6) (individual) cells.

These "individual" Lead cells have a:
... (low) voltage threshold of ~1.75V
...a (nominal) voltage of ~2V
...the (high or max) voltage is ~2.21V
…with a (usable) voltage range of only ~0.46V

So, the voltage limits for a (standard) 12V Lead battery "module" would be:
...(low) ~10.5V
…(nominal) ~12V
...the (max) is ~13.3V
…with a (usable) voltage range of ~2.8V

Takin' it a step further, if (2) 12V battery "modules" are connected together "in series" you would have a 24V "battery pack"
…(3) 12V "modules" would make up a 36V "pack"
…& (4) of them would make up a 48V "pack" etc.

Lead Battery Module/Pack Voltage Ranges

Voltage___Low____Nominal___High____Usable

12V______~10.5V____~12V____~13.3V___~2.8V
24V______~21V_____~24V_____~26.6V___~5.6V
36V______~31.5V___~36V_____~39.9V___~8.4V
48V______~42V_____~48V_____~53.2V___~11.2V
60V______~52.5V___~60V_____~66.5V___~14V
72V______~63V_____~72V_____~79.8V___~16.8V
 

Functional Artist

Active member
Messages
2,599
Reaction score
20
Location
Toledo, Ohio
Ok now, let's discuss the parameters of small DCV (Direct Current Voltage) systems :thumbsup:

It seems that the voltage specs for most of these small DCV systems, that were working with, is based on the voltage specs of Lead Acid batteries
(I guess, mainly, because they were mostly the only type of battery that was commercially available for many years)

Something like this: :cheers2:

DC System Voltage Ranges

Voltage___Low____Max

12V______~10.5V____~20V
24V______~21V_____~32V
36V______~31.5V____~44V
48V______~42V_____~56V
60V______~52.5V___~68V
72V______~63V_____~80V

We have a pretty good idea of the low V specs, from the Lead Battery Module/Pack Voltage Ranges chart
…& the Max is kind of a "guestimate" of what these small DCV systems should be able to safely handle :idea2:

Why is this important?

It's important because a lot more of us/we/folks want to use Lithium battery packs on our DIY karts
...or when converting a "gas" kart to electric
...&/or even when upgrading an electric kart/minibikes etc. from Lead battery packs upto lithium packs

But, there are a lot of different battery chemistry types (as discussed above)
…with (sometimes) large voltage differences between those different battery chemistry types
…plus, the battery cells can be set up in many different configurations (14S, 15S, 16S etc.)
…& (usually) there are other variables (differences in dis-charge & charging rates) that really need/must be "factored in" to use these "super powerful batteries" SAFELY :cool:
...especially when "posting" info that others may try/follow :2guns:
 

Tpdingo

Member
Messages
903
Reaction score
0
Location
Bellmore, NY
I think we can sum your entire thread into 3 lines.

Google the battery you would like to use.
Read it's datasheet and find the appropriate charger and safety equipment
Treat the battery like your first born kid regardless of chemistry.
 

Functional Artist

Active member
Messages
2,599
Reaction score
20
Location
Toledo, Ohio
I think we can sum your entire thread into 3 lines.

Google the battery you would like to use.
Read it's datasheet and find the appropriate charger and safety equipment
Treat the battery like your first born kid regardless of chemistry.

Simple as "Google the battery you would like to use" huh ? :huh:
..but, there's a ba-zillion different types & other variables too
...& it seems like that's where most folks get stuck
...or start heading down the wrong path
...or at least not the best path

So, where does "one" start? :idea2:

Example:
OK Um... I want to use a 48V 1,000W system on my kart :thumbsup:
...so, I'll just Google "What battery to use on a go kart with a 48V 1,000W motor?"

The first thing that came up was:

"Unit Pack Power Electric Bike Battery
- 48V Ebike Battery for 1500W/1000W/500W Bicycle DIY
- Best Lithium ion Battery for Bafang Motor(48V 20Ah/ 52V 14Ah)

This triangle Ebike battery is 52V 20AH, suitable for 1000W/500W motor.
Max constant discharge current:30A.
Size:10.3×6.3×2.8 in.
Charger: 54.6V 2.5A US Plug"

https://www.amazon.com/UnitPackPowe...&hvlocphy=&hvtargid=pla-4584276304003878&th=1

But, in the same ad it shows a 48V 20AH bat pack w/30A BMS $335.50
…a 48V 20AH bat pack w/50A BMS $355.50
…& a 52V 20AH bat pack w/30A BMS $358.00 (probably a typo & it's really 14AH)

So, do we know what the voltage is, of the cells, that this pack is constructed of? No
...what about the materials those cells are constructed from No, again
...or how those cells are configured? (12S, 6S2P etc.) Nope, no clue

Does it come with the appropriate charger? (the ad mentions: "Charger: 54.6V 2.5A US Plug")
...but, it doesn't specify "if" that charger is included :ack2:

Nope, that's NOT confusing, at all :rolleyes:
…& that's just the first one :roflol:

Now, what happens after the average Jo, reads thru a few of those "Google" results (ad's, videos etc.)

Um...help :surrender:

Yup, their way more confused than when they started :mad2:

That why I started this thread
...to help me & others understand this stuff better :cheers2:

IMO
"Don't just hand someone a fish, show them how to fish" :2guns:
 

Functional Artist

Active member
Messages
2,599
Reaction score
20
Location
Toledo, Ohio
Personal commentary

I've been thinkin' about it :idea2:
...& I think I figured out how/why I had that Lithium battery stuff all wrong :huh:

First, keep in mind that forever & ever, the main "big" battery type was based upon Lead Acid chemistry
…& they were almost always configured in 12V packages (packs)

There were also Industrial batteries available, configured into 6V packages, for like fork lifts & golf carts
…they were of the Lead Acid type too
…& they were usually connected in series to form higher voltage packs (multiples of 12V like 36V, 48V etc.)

But, there was NOT a lot of other variations to deal with
...mainly, just match-up the voltages

So basically, you could just use (1) 12V battery to power a 12V system & then, a 12V charger to charge it back up (like automobiles)
…or use (2) 12V batteries wired "in series" to power a 24V system & a 24V charger, to charge them up
…or (4) 6V battery "modules" "in series" could also be used to power 24V systems etc.,etc. :cheers2:


So, when I was researching, to learn more about Lithium batteries, it looked like with this "new" technology, there were (2) "main" but, very different types, LiPo & LiMag

To me, it seemed like the LiPo cells,
...were made with Lithium & Potassium
...packaged in round containers
...& had a 3.2V (Nominal) voltage rating
...like the famous 18650's

& then, there were these LiMag cells
...that were made with Lithium & Magnesium
...packaged in Pouch type containers
...with a 3.7V (Nominal) voltage rating
...like used in the Chevy Volt & Nissan Leaf automotive battery packs

* So, I guess that, I figured it was kinda like, back when VCR's (video cassette recorders) first came out
...& there was (2) "main" but, very different competing types available, VHS & Beta

But, that's NOT the end of the story because there are so many more variables (chemistries, voltages, packaging etc.) :ack2:

So, now I (& hopefully anyone who reads this) understands that the most important things to know, when working with lithium batteries
...is to "BE AWARE" of, learn & understand what the specifications are for the specific type of lithium cells, that you want to use :thumbsup:
…& follow those specifications, to the letter
..."Treat the battery like your first born kid" as Tpdingo has suggested
…& always remember, as Sid had made clear "LiIon cells are NOT LiIon cells!!!"
 

Functional Artist

Active member
Messages
2,599
Reaction score
20
Location
Toledo, Ohio
DIY battery packs

Now, lets look into some of the details that are involved, with building a DIY battery pack :thumbsup:

First, keep in mind, "factory made" battery cells (AA, AAA, 9V, 18650's etc.)
…& battery packs (12V automotive, 36V E-bike batteries etc.) have been designed & manufactured by professionals

Which means that a trained professional has "done the math" & contemplated many factors that need to be incorporated into the mix like:
... pack voltage
...amp ratings (dis-charging & charging)
...pack capacity
...& even resistance

Next, materials are thoughtfully chosen
...then, those materials are professionally assembled
...& finally, the "end product" gets thoroughly tested, before being "released" for public use

So, "if" these factory made battery/packs are treated & used "as directed" there's usually not a lot, for the end user, to "think" or worry about :cheers2:


Now, to build a DIY batt pack yourself, "you" have to be the "trained professional" (so to speak)
...& wear all of the different "hats" :cool:

The designer
...& "do the math" to account for all of the factors involved, with "your" specific situation

The parts chooser
…& pick compatible parts that match "your" specific system's specs
(don't forget that ya gotta factor in some of the other important details like weight, size & even the total cost)

The assembler
...to arrange & assemble the components

& the tester
...put 'er on your kart & try 'er out (the best part) :2guns:
 

Functional Artist

Active member
Messages
2,599
Reaction score
20
Location
Toledo, Ohio
YX YH DC 48V35Ah Ternary lithium Battery Pack

While lookin' for a reasonably priced, professionally designed & factory built 48V lithium battery pack, I came across a Ternary lithium Battery Pack (48V 35Ah) for (up to) an 1800W motor
...that has a built in BMS (battery management system)
...& comes with a "proper/matching" (5A) charger (for under $400.00) :thumbsup:

YX YH DC
48V 35Ah Ternary lithium Battery Pack
(~$375.00)
https://www.ebay.com/itm/48V35Ah-Te...e=STRK:MEBIDX:IT&_trksid=p2057872.m2749.l2649

Description
ENERGY THE ELECTRIC ADVANTAGE
* Rated Voltage: 48V
* Nominal Voltage : 51.2V
* Capacity (amp hours) : 35Ah
* Continuous Discharge current : 50A

SIZE & WEIGHT ADVANTAGE
* Size (L x W x H): 280*180*85mm/11.1*7.1*3.4inch
* Weight: About 9.35KG/20.6lb

TECHNOLOGY ADVANTAGE
* Usable Capacity (AH): 35AH
* Depth of Discharge : 100% DOD
* Automatic Over Voltage Protection : 58.4V
* Reserve Minutes @ 10A 6 min
* Self Discharge <3% per month

SAFETY & PROTECTION ADVANTAGE
* Built in Automatic Battery Protection System Internal
* Automatic Short Circuit Protection Instant
* Flame Retardant Electrolyte : Yes
* Length Way Circuit Boards : Yes
* Automatic Internal Cell Balancing : Yes
* Explosion Proof Polymer Cells :Yes

Features
* Fully automatic built in battery protection system
* Long life 1000 - 2000 cycles
* Lightweight - up to 70% lighter than lead
* No voltage sag - faster cranking for motors and higher voltage for continuous consistent power.
* Dry Battery - no toxic lead or acid
* Green ROHS compliant - No Lead
* Does not heat up during use

Package List
1 x 48V 35AH Lithium Li-ion Battery Pack
1 x 54.6V 5A Charger
1 x 50A BMS (BMS is built in the battery pack)
2 x Anderson plug(discharge)
1 x Three-hole charging plug
1 x charger Operating instruction
n

This 48V 35AH Ternary lithium Battery Pack should have like (3) times the capacity of the (4) 12V 12AH SLA's that I have in my kart
...& also, should be able to handle the "strain" (ie. voltage drop) from hard acceleration better too :cool:

For comparison, a 48V 35AH SLA pack would be (12) 12V 12AH modules, which all together
...would occupy a space (~16"W x 18"D x 4"H) :huh:
...weigh over 100lbs. (~10lbs. x 12 = 120lbs.) :ack2:
...& cost ~$300.00 (12 SLA's x $25.00ea. = $300.00) :mad:

Whereas this Ternary pack
...occupies ~11"W x 7"D x 3.5"H
...weighs ~20lbs.
...but, only costs ~$75.00 more
...& don't forget, it includes the matching charger :2guns:


Lets double check the specs of this batt pack, to see how/if it "matches up" with our system

Both are 48V ...check
My (MY-1020) 48V 1,000W brushed motor is rated to draw ~20A
...& will maybe draw ~40A max (during peaks or "bursts" upon hard accelerations)

This pack with it's 50A continuous
...& 75A max ratings, seem to easily meet the specifications of our system :bannana:

So, Ima gonna give one a try :stir:
 

Attachments

  • SAM_6041.JPG
    SAM_6041.JPG
    314.7 KB · Views: 1
  • SAM_6042.JPG
    SAM_6042.JPG
    304.9 KB · Views: 1
  • SAM_6043.JPG
    SAM_6043.JPG
    312 KB · Views: 1
  • SAM_6044.JPG
    SAM_6044.JPG
    324.1 KB · Views: 2
  • SAM_6045.JPG
    SAM_6045.JPG
    318.8 KB · Views: 1
  • SAM_6046.JPG
    SAM_6046.JPG
    305.2 KB · Views: 1
  • SAM_6047.JPG
    SAM_6047.JPG
    318.7 KB · Views: 2
  • SAM_6048.JPG
    SAM_6048.JPG
    315 KB · Views: 0
  • SAM_6049.JPG
    SAM_6049.JPG
    318 KB · Views: 0
  • SAM_6058.JPG
    SAM_6058.JPG
    306.3 KB · Views: 0

EpsilonZero

...still cheaper than a boat!
Messages
94
Reaction score
24
I would be sure to charge it off the kart in a place that won't "light up your life". :popcorn:
 

Functional Artist

Active member
Messages
2,599
Reaction score
20
Location
Toledo, Ohio
I would be sure to charge it off the kart in a place that won't "light up your life". :popcorn:

What would be your concern? :huh:
...just the chemistry? :popcorn:

It's professionally designed & built :thumbsup:
...with all new materials
...including a "built in" BMS
...& also, comes with the matching charger :2guns:

I'ma gonna test/try it, on the Excalibur kart (dual 48V 1,000W motors) :stir:
 

itsid

Moderator
Staff member
Messages
11,522
Reaction score
67
Location
Ruhrpott [Germany]
nice battery (well ugly.. but as if design would matter ;))
too bad it didn't come with proper labelling (what chemistry, what peak/cont discharge etc...)

Anyways.. seems good..
still I think taking reasonable precautions as epsilon suggested isn't a bad idea
no matter the battery and or charger..
charging it in a cool dry place a safe distance apart from beloved and precious,
not allowing the charger to overcharge (the green check light being on for too long)
just in case..
you know just the standards ;)

'sid

PS we need this thread to be cleaned and renamed...
I'll take a note and see what I can be done when the temp drops tonight)
 

EpsilonZero

...still cheaper than a boat!
Messages
94
Reaction score
24
What would be your concern? :huh:
...just the chemistry? :popcorn:

It's professionally designed & built :thumbsup:
...with all new materials
...including a "built in" BMS
...& also, comes with the matching charger :2guns:

I'ma gonna test/try it, on the Excalibur kart (dual 48V 1,000W motors) :stir:

What kind of cells (brand, model, chemistry)? What configuration are they in (#S/#P)? Not that there couldn't be counterfeit cells in there, but I don't see where they provide any information at all. There is no telling if the specs they give are legitimate and no telling what kind of quality there is in the package. If they provided the cell specs and configuration, you could work out the numbers yourself. Not that these two manufacturers are necessarily the best, but look at the detail that is provided.

https://em3ev.com/shop/50v-14s7p-rectangle-battery-pack/
https://lunacycle.com/52v-samsung-30q-12ah-high-power/

You might be able to power your kart with that pack with no problems, but I wouldn't bet my kart or the building it is in on it. I'm just saying you should take precautions if you're going to gamble on something that could explode and burn. Even with a reputable manufacturer, I would remove a LiPo (non-LiFePO4) pack to a safe location for charging.
 

Functional Artist

Active member
Messages
2,599
Reaction score
20
Location
Toledo, Ohio
What kind of cells (brand, model, chemistry)? What configuration are they in (#S/#P)? Not that there couldn't be counterfeit cells in there, but I don't see where they provide any information at all. There is no telling if the specs they give are legitimate and no telling what kind of quality there is in the package. If they provided the cell specs and configuration, you could work out the numbers yourself. Not that these two manufacturers are necessarily the best, but look at the detail that is provided.

https://em3ev.com/shop/50v-14s7p-rectangle-battery-pack/
https://lunacycle.com/52v-samsung-30q-12ah-high-power/

You might be able to power your kart with that pack with no problems, but I wouldn't bet my kart or the building it is in on it. I'm just saying you should take precautions if you're going to gamble on something that could explode and burn. Even with a reputable manufacturer, I would remove a LiPo (non-LiFePO4) pack to a safe location for charging.

Hey EZ,
I appreciate your concerns :thumbsup:
...& you bring up many good points :cheers2:

So, I sent a message, to the retailer that I bought this battery from :cool:

Hello,
I bought this battery pack last month & would like some info on it's construction.
(so, that I know what I have)
What kind of cells (brand, model, chemistry)?
...& what configuration are they arranged in (#S/#P)?
Thanks, Kevin


...& this was their response :popcorn:

The brand of the cells is "BAK", "soundon",
They are a very famous new energy company with a professional R&D team and high-tech. They has been engaged in the research and production of new energy batteries for 20 years.
The chemical composition of the battery is a ternary lithium polymer.
The battery is made up of 13pcs 3.7V 35Ah batteries connected in series(13S 1P)
Best wishes to you and your family.


Also, found this:

What Is A Ternary Lithium Battery? (Jun 26, 2019)
In nature, lithium is the lightest metal with the smallest atomic mass. Lithium is chemically active, and it is easy to lose electrons to be oxidized to Li+. The standard electrode potential is -3.045V, and the electrochemical equivalent is 0.26g/Ah. These characteristics determine that it is a material with a very high specific energy. The ternary lithium battery refers to a lithium secondary battery using three kinds of transition metal oxides of nickel, cobalt and manganese as a positive electrode material. It fully integrates the good cycle performance of lithium cobaltate, the high specific capacity of lithium nickelate and the high safety and low cost of lithium manganate. It synthesizes nickel by molecular level mixing, doping, coating and surface modification. A multi-element synergistic composite lithium intercalation oxide such as cobalt manganese is a lithium ion rechargeable battery that has been widely studied and applied.

https://www.chilweebattery.com/news/what-is-a-ternary-lithium-battery-24647699.html

Don't worry, I ain't lookin' for trouble :innocent:

As with ALL Lithium batteries
...I'ma gonna take ANY & ALL necessary precautions :2guns:
 

EpsilonZero

...still cheaper than a boat!
Messages
94
Reaction score
24

The battery is made up of 13pcs 3.7V 35Ah batteries connected in series(13S 1P)

I don't think you can get 35Ah out of a 13S1P pack unless I am way behind on my battery technology. I could see 3500mAh, which is a cell they have at 3.7v. Are there really only 13 cells in that pack? If they are 3500mAh cells, you'd need 13s10P to get 35Ah. Probably a typo.

http://www.bak-tech.com/products/show-354.html

I couldn't find any stats on charge/discharge rates for the cell (not a good sign), but 50A continuous discharge in a 10P pack is typically achievable.
 

Functional Artist

Active member
Messages
2,599
Reaction score
20
Location
Toledo, Ohio
I went ahead & tested the YX YH DC 48V 35AH Lithium battery pack on the Excalibur kart. :)
...but, I had to abort the test @ only 250Wh used because the out put cables were getting warm & the corner of the batt pack (where the cables come out) was getting increasingly warmer/hot too. :cautious:


Hmmm...doesn't seem like it can "safely" power (2) 1,000W motors

* It was listed as: Ternary lithium Battery Pack (48V 35Ah) for (up to) an 1800W motor)
...but, the specs said it could discharge 50A cont. & 75A max (I guess that was a "bit inflated") :unsure:

Well, let's see what this batt pack can do if I remove (1) of the 48V 1,000W motors
...so, I charger 'er back up & tested 'er again :sneaky:


Then, after the "mechanical failure" (broke a spindle bracket off) I resumed testing this batt pack :cool:


After ~3hrs (total) of practically "full throttle" driving, I ended up gettin' ~1,350 Wh of energy out of this pack :2guns:
...with the meter still showing ~46V
...& she was still "zippin'" around pretty well :cool:

I must say, so far this batt pack seems pretty "Bad Azz"
...& it seems to power (1) 48V 1,000W motor really well, without any issues
 
Messages
67
Reaction score
3
Location
Albany, OR
I don't think you can get 35Ah out of a 13S1P pack unless I am way behind on my battery technology. I could see 3500mAh, which is a cell they have at 3.7v. Are there really only 13 cells in that pack? If they are 3500mAh cells, you'd need 13s10P to get 35Ah. Probably a typo.

http://www.bak-tech.com/products/show-354.html

I couldn't find any stats on charge/discharge rates for the cell (not a good sign), but 50A continuous discharge in a 10P pack is typically achievable.
I saw a website that ran 15S5P for 30AH, they were 32700 or something like that, 3.2V nominal, fat cells, LiFePO I think. I can't remember the output, I think it was 50A continuous?
 
Top