Battery care and safety

wicky_boy

Just Joined
Mar 22, 2019
3
1
I recently had an ebike battery "serviced" (they did the work without asking then charged me). I was told that the soldered the inner and outer pair of terminals together on a hailing battery to ensure that the connections work as I have been have cut out issues which have been blamed on battery connectivity to the cradle.

When they returned the battery to me after I part payed for the the work and postage they sent me a pamphlet about battery safety.

In the pamphlet about battery safety there is a disclaimer that says unless the battery is kept per instructions they take no responsibility for damage incurred. One of their instructions is to keep it OUTSIDE!

What gives? Are these Hailong batteries really that dangerous? Does anyone have any experience with exploding Hailong ebike battery packs?
 

Nealh

Esteemed Pedelecer
Aug 7, 2014
7,864
2,967
56
West Sx RH
With some people there is a fear that batteries catch fire, the same can be said of your phone, tablet, pc and even vacuum cleaner etc etc, do you keep them out side !!!
And what are the instructions ?
 

Andy-Mat

Esteemed Pedelecer
Oct 26, 2018
504
94
72
I recently had an ebike battery "serviced" (they did the work without asking then charged me). I was told that the soldered the inner and outer pair of terminals together on a hailing battery to ensure that the connections work as I have been have cut out issues which have been blamed on battery connectivity to the cradle.

When they returned the battery to me after I part payed for the the work and postage they sent me a pamphlet about battery safety.

In the pamphlet about battery safety there is a disclaimer that says unless the battery is kept per instructions they take no responsibility for damage incurred. One of their instructions is to keep it OUTSIDE!

What gives? Are these Hailong batteries really that dangerous? Does anyone have any experience with exploding Hailong ebike battery packs?
You write a very interesting post, which I will follow as others post here, though I do not know the name of the cell supplier at all myself.
It seems a bit naughty to do work without an authorisation and also charge for it too, that will not gain them happy customers....
Did you carefully read through their terms of service?
I have (unintentionally at first, but now intentionally), only have had Panasonic cells in the total of 3 batteries I have owned for both of my e-bikes.
None were a problem.
The first one was well over 6 years old when I gave the bike away, with barely any noticeable loss of "distance" over those years! Though it happens so slowly, I may not have noticed....but more than 5 KMs it was not, but difficult to judge accurately!
I have seen a few videos of the problems some batteries have had, on YouTube for example, but I do not remember ever seeing the name of the cell manufacturer mentioned, so I have no personal "feelings" either way, but hopefully a few here know more!
I assume that you are fully aware of what CAN happen with a Li-ion celled battery, especially if mechanically damaged. You would not want that to happen in your house believe me.....Smoke sensor over the battery might be a sensible solution...
I guess they are just being careful, and maybe their business insurance requires that they inform customers, who knows?
But you could ask them if that is for all cells, or just that particular manufacturer!
regards
Andy
PS. Someone on this Forum, a long time ago, was talking about manufacturers "grading" cells, for building batteries. And the bad cells that did not make the grade, were sold off to bike shops and the like.....who were IMHO, therefore building fire bombs, not batteries!! I could not find the topic again, sorry!
regards
Andy
 

Woosh

Trade Member
May 19, 2012
11,432
8,653
Southend on Sea
wooshbikes.co.uk
What gives? Are these Hailong batteries really that dangerous? Does anyone have any experience with exploding Hailong ebike battery packs?
yes, all batteries are dangerous because they store enough energy to boil a kettle or two and you'll find the warning triangle stickers on them.
The risk is small, but real.
The Hailong are good designs, they use more or less exclusively cylindrical cells with steel jacket, very safe in comparison with the soft pouch cells of yesteryear.
Technology improves all the time, 10 years ago, the BMS used to burn milliamps 24 x 7, only the most sophisticated batteries had hibernation function. You had to top up charge every 2-3 months.
Now all batteries have hibernation function, you can store the battery for the whole year or even 2 without topup charging.
The best state of charge for storage is between 50% and 75% full.
Before you topup charge your battery, make sure that they are less than 50% full. If your battery indicator has 5 bars, don't top up until it loses 3 bars out of 5 and charge only up to 4 bars out of 5 you you are not going to use it for a few months.
many users don't realise is that batteries are mechanical devices. They use a mechanism called intercalation, moving Lithium from one electrode to the other, swelling up the destination electrode and causing them slowly but surely to break down in time. They degrade fastest when 100% full or completely flat.
If you don't top up charge, then the risk is minimal but if you do, then you increase the risk of breakdown because your battery is more likely to become unbalanced and overcharged.

If your battery is more than 5 years old, think of replacing it. In 5 years, the cell density and reliability have about doubled, it's well worth it.
 
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Laser Man

Pedelecer
Jul 1, 2018
125
74
Michelmersh SO51
The Dutch bike company Stella has had several very serious fires involving ebikes and their batteries.
(It's not clear whether batteries caused the fires, but that seems likely).

500Wh = 180,000 W/seconds - a LOT of energy if something goes wrong!

I only charge our batteries when I'm around to supervise (i.e. not overnight) and store the bikes in the garage where a fire would be a nuisance but not a life-threatening disaster.
 

Darren Hayward

Finding my (electric) wheels
Mar 25, 2015
21
4
56
How do you store a battery outside in the winter? Isn't the standard advice to NOT store the battery in sub zero temperatures? Certainly my TransX battery says that. My Bosch I assumed would be the same.


Darren
 

Woosh

Trade Member
May 19, 2012
11,432
8,653
Southend on Sea
wooshbikes.co.uk
How do you store a battery outside in the winter? Isn't the standard advice to NOT store the battery in sub zero temperatures? Certainly my TransX battery says that. My Bosch I assumed would be the same.
Darren
You should store it where it can only cause a minimal damage, in a dry and ventilated room, away from inflammable materials.
They are safe between -15C and 40 degrees Celsius.
Modern cells are also much safer than before, they all have anti-explosion and anti thermal runaway features.
 

vfr400

Esteemed Pedelecer
Jun 12, 2011
2,133
541
Basildon
If you sent in a battery for service because it was cutting out and they soldered the pairs of terminals, that's entirely reasonable and sensible, but you only get the benefit if they paired them up on the receiver side as well. Did you send in the receiver with the battery or just the battery?
 

D C

Esteemed Pedelecer
Apr 25, 2013
936
429
Cairngorm National Park
They are safe between -15C and 40 degrees Celsius.
I didn't realise batteries are okay down to minus 15, my shed sometimes gets down to minus 10 in winter.
Is it not harmful to charge at such a low temperature? I've always kept and charged my Hailong battery (part of my Woosh kit) indoors in a cool area during the winter months.
Dave.
 

Woosh

Trade Member
May 19, 2012
11,432
8,653
Southend on Sea
wooshbikes.co.uk
I didn't realise batteries are okay down to minus 15, my shed sometimes gets down to minus 10 in winter.
Is it not harmful to charge at such a low temperature? I've always kept and charged my Hailong battery (part of my Woosh kit) indoors in a cool area during the winter months.
Dave.
from Samsung datasheet:
Operating Temperature: (Cell Surface Temperature) Charge: 0°C to 45°C, Discharge: -20°C to 60°C
Storage Temperature: 1 year : -20°C~25°C, 3 months : -20°C~45°C. 1 month : -20°C~60°C

You should charge it at above 0°C but can store it at much lower temperature.
The electrolyte itself freezes at -40°C.
 
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KirstinS

Esteemed Pedelecer
Apr 5, 2011
2,768
710
Brighton
I cant add much to what's been said already

I charge indoors but only when present and about 2 foot from a smoke/fire alarm

This includes home built battery packa which I assume to be less safe although i build the same with bms and kapton tape before heat shrink

Though, on occasion, I have been known to test charge packs via extension leads at the bottom of the garden under large empty planter !
 

Nealh

Esteemed Pedelecer
Aug 7, 2014
7,864
2,967
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West Sx RH
My batteries for added protection I now use only the 20mm spacers to build my packs, top and bottom of pack I use 0.8mm epoxy glass sheet and fibreglass tape as binding before shrink wrapping.
 

wicky_boy

Just Joined
Mar 22, 2019
3
1
You write a very interesting post, which I will follow as others post here, though I do not know the name of the cell supplier at all myself.
It seems a bit naughty to do work without an authorisation and also charge for it too, that will not gain them happy customers....
Did you carefully read through their terms of service?
I have (unintentionally at first, but now intentionally), only have had Panasonic cells in the total of 3 batteries I have owned for both of my e-bikes.
None were a problem.
The first one was well over 6 years old when I gave the bike away, with barely any noticeable loss of "distance" over those years! Though it happens so slowly, I may not have noticed....but more than 5 KMs it was not, but difficult to judge accurately!
I have seen a few videos of the problems some batteries have had, on YouTube for example, but I do not remember ever seeing the name of the cell manufacturer mentioned, so I have no personal "feelings" either way, but hopefully a few here know more!
I assume that you are fully aware of what CAN happen with a Li-ion celled battery, especially if mechanically damaged. You would not want that to happen in your house believe me.....Smoke sensor over the battery might be a sensible solution...
I guess they are just being careful, and maybe their business insurance requires that they inform customers, who knows?
But you could ask them if that is for all cells, or just that particular manufacturer!
regards
Andy
PS. Someone on this Forum, a long time ago, was talking about manufacturers "grading" cells, for building batteries. And the bad cells that did not make the grade, were sold off to bike shops and the like.....who were IMHO, therefore building fire bombs, not batteries!! I could not find the topic again, sorry!
regards
Andy
Yes it was a bit naughty. There was another naughty "not-best-practice" procedure that I won't mention that sent my alarm bells ringing . I won't mention who it was. Its a small world though isn't it? :)
 

wicky_boy

Just Joined
Mar 22, 2019
3
1
Thanks for all your replies! Very informative! I think I'll keep it in the kitchen on my bike in the cradle hanging up away from the wall. There's a piercing loud fire alarm in there that will give you tinnitus for a week.
 
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