need help for battery analysis

Batteries, Chargers, and Battery Management Systems.
Post Reply
kilowat   100 µW

100 µW
Posts: 9
Joined: Nov 06 2014 2:31pm

need help for battery analysis

Post by kilowat » Mar 12 2018 2:54pm

I need your experience, I'm about to buy a battery, on a seller, I ask the state of the batteries, apparently Chinese batteries "sanyo"
what do you think about these sanyo batteries?
are 48v40ah batteries .
"They are from Sanyo with 2 years guarantee;
I also tested them out of the output with a multimeter in series: voltage started max 53.6 and gradually fell empty to 45.3V.
I trust the supplier of the batteries: it is a serious company

is it normal that the voltage drops as much ?

User avatar
fechter   100 GW

100 GW
Posts: 12894
Joined: Dec 31 2006 3:23pm
Location: California Bay Area, USA

Re: need help for battery analysis

Post by fechter » Mar 12 2018 3:22pm

"Real" Sanyo batteries are good quality. Just not rated for super high discharge current. 40Ahr is a very large battery.

The voltage range you show is quite normal going from full charge to empty (indicates 13 series cells).
"One test is worth a thousand opinions"

DAND214   1 GW

1 GW
Posts: 3074
Joined: Aug 10 2008 8:28pm
Location: About 1200 miles south of Chicago, in sunny/rainny Port Richey, Florida!

Re: need help for battery analysis

Post by DAND214 » Mar 12 2018 4:00pm

kilowat wrote:
Mar 12 2018 2:54pm
I need your experience, I'm about to buy a battery, on a seller, I ask the state of the batteries, apparently Chinese batteries "sanyo"
what do you think about these sanyo batteries?
are 48v40ah batteries .
"They are from Sanyo with 2 years guarantee;
I also tested them out of the output with a multimeter in series: voltage started max 53.6 and gradually fell empty to 45.3V.
I trust the supplier of the batteries: it is a serious company

is it normal that the voltage drops as much ?
Can you supply the sellers name/company?

Dan

kilowat   100 µW

100 µW
Posts: 9
Joined: Nov 06 2014 2:31pm

Re: need help for battery analysis

Post by kilowat » Mar 12 2018 5:27pm

I will ask more information to the seller and I will come back to you
regarding the discharge up to 45v, a 48v battery should not stay at least 48v?
thank you

DAND214   1 GW

1 GW
Posts: 3074
Joined: Aug 10 2008 8:28pm
Location: About 1200 miles south of Chicago, in sunny/rainny Port Richey, Florida!

Re: need help for battery analysis

Post by DAND214 » Mar 12 2018 10:53pm

kilowat wrote:
Mar 12 2018 5:27pm
I will ask more information to the seller and I will come back to you
regarding the discharge up to 45v, a 48v battery should not stay at least 48v?
thank you
48V Is just the nominal voltage, which is close to the middle of the upper and lower voltage of the cells. 45v would be the low end of the cell voltage and 53/54 is the top voltage.
Normal.

Dan

User avatar
amberwolf   100 GW

100 GW
Posts: 25101
Joined: Aug 17 2009 6:43am
Location: Phoenix, AZ, USA, Earth, Sol, Local Bubble, Orion Arm, Milky Way, Local Group
Contact:

Re: need help for battery analysis

Post by amberwolf » Mar 13 2018 1:32am

If you really want a good technical opinion, you must link us to the battery sale page so we can see it's specs/etc.

It all sounds pretty normal, but as noted above, it's a really big and heavy battery. Probably weighs close to 30-35lbs or more.

You don't want that on a rear rack. ;) And it's unlikley to fit in a triangle bag or box.

kilowat   100 µW

100 µW
Posts: 9
Joined: Nov 06 2014 2:31pm

Re: need help for battery analysis

Post by kilowat » Mar 14 2018 11:00pm

hi
caracteristique :
Standard voltage: 48v
Nominal capacity: 13.2Ah
Standard continuous discharge current: 1.1A
Maximum continuous discharge current: 2.2A
Working temperature: Charging: 0 ~ 45 ℃; Discharge: -20 ~ 60 ℃
Product Size: 35 * 35 * 70mm
Cycle life: 500 times
Output mode: UL1007 / 22AWG line length 60mm (can be customized according to customer requirements)
Main protection function: overcharge protection, over discharge protection, short circuit protection, overcurrent protection, current balance, over temperature protection

the batteries were bought at king-energy.com

thanks

User avatar
fechter   100 GW

100 GW
Posts: 12894
Joined: Dec 31 2006 3:23pm
Location: California Bay Area, USA

Re: need help for battery analysis

Post by fechter » Mar 14 2018 11:25pm

kilowat wrote:
Mar 14 2018 11:00pm

Standard voltage: 48v
Nominal capacity: 13.2Ah
Standard continuous discharge current: 1.1A
Maximum continuous discharge current: 2.2A
Cycle life: 500 times
Output mode: UL1007 / 22AWG line length 60mm (can be customized according to customer requirements)
Main protection function: overcharge protection, over discharge protection, short circuit protection, overcurrent protection, current balance, over temperature protection
Well, not quite 40Ah.

2.2A discharge current seems extremely low for a battery this size. Something seems wrong about those numbers.
22AWG wire is about right for 2.2A.

This will not power a bike. What is your application?
"One test is worth a thousand opinions"

999zip999   100 GW

100 GW
Posts: 8346
Joined: Jan 10 2010 1:40pm
Location: Dana Point So. Cal

Re: need help for battery analysis

Post by 999zip999 » Mar 15 2018 12:58pm

How about a link that you are viewing?

kilowat   100 µW

100 µW
Posts: 9
Joined: Nov 06 2014 2:31pm

Re: need help for battery analysis

Post by kilowat » Mar 15 2018 3:20pm

yes sorry

http://www.king-energy.com/default2-nam ... e]pack.htm


I am a novice and I notice in fact that the wire is abnormally too thin, especially since I had the idea of pairing two 48v 40ah batteries to put in a stealth bomber 52, this is not going to do I think?

the person has several batteries,
I had two ideas for two different bikes

first bike: a suspended full which I would like to install a kit bbshd 1000w.
second bike: an old stealth 52 bomber of 2013 whose battery was not charged correctly and found it unusable.

User avatar
fechter   100 GW

100 GW
Posts: 12894
Joined: Dec 31 2006 3:23pm
Location: California Bay Area, USA

Re: need help for battery analysis

Post by fechter » Mar 15 2018 11:27pm

The battery in the ad will not be suitable for a bike of any kind. Way too low current rating.
"One test is worth a thousand opinions"

User avatar
amberwolf   100 GW

100 GW
Posts: 25101
Joined: Aug 17 2009 6:43am
Location: Phoenix, AZ, USA, Earth, Sol, Local Bubble, Orion Arm, Milky Way, Local Group
Contact:

Re: need help for battery analysis

Post by amberwolf » Mar 16 2018 12:37am

kilowat wrote:
Mar 15 2018 3:20pm
http://www.king-energy.com/default2-nam ... e]pack.htm
I am a novice and I notice in fact that the wire is abnormally too thin, especially since I had the idea of pairing two 48v 40ah batteries to put in a stealth bomber 52, this is not going to do I think?
As has already been pointed out, that is not a 40Ah battery.

In fact, the page has at least two contradictory capacities--it is titled as a 20Ah battery, but the "specs" say it is 13Ah.

Whether it is just a mistake or a deception, either one makes the seller untrustworthy and I would not purchase anything from them (because you cannot trust *anything* any of their pages say about any of their products).

Even if they were trustworthy, that battery is (as others have said) completely insufficient for EV motor use.

You would have to parallel 40 or 50 them to get any reasonable current out of them for a high powered bike like the Stealth series, and at that point you'd need a trailer to carry them.

I'd recommend checking out http://ebikes.ca or maybe Luna or even Allcell, for ebike batteries.

But before you look into a battery, you first need to know what the current (amp, A) requirements are for the bike it's for. Then you have to see if the battery you are looking at can handle that.

User avatar
dogman dan   100 GW

100 GW
Posts: 34366
Joined: May 17 2008 12:53pm
Location: Las Cruces New Mexico USA

Re: need help for battery analysis

Post by dogman dan » Mar 16 2018 6:05am

Too many red flags for you to buy that one. Confusing specs just mean you send money, then they send something, whatever.

Zero chance you get what you thought you bought.

kilowat   100 µW

100 µW
Posts: 9
Joined: Nov 06 2014 2:31pm

Re: need help for battery analysis

Post by kilowat » Mar 16 2018 11:17am

arf
I understand better now why the salesman wants to get rid of it.
I abandon this track in this case.
thanks guys ! :)

Post Reply