General e-bike function questions

Croxden

Esteemed Pedelecer
Jan 26, 2013
2,134
1,384
North Staffs
My Bosch battery is cold in the morning, the charger perhaps one degree warmer.

I would trust Bosch over the 'Chinese' types.
 

flecc

Member
Oct 25, 2006
52,880
30,419
I wonder if it would over charge or something? The light goes green when it's done but not sure if that means it stops charging
That does mean it's stopped charging. Unlike with some other battery types, chargers for lithium batteries are not smart. It's the batteries own internal BMS (battery management system) that turns off the charge when full. When the BMS stops the charge, the charger not being able to deliver any more will change it's LED indication to charge finished.

In the late stages of charging a BMS can top up cells individually if necessary to even up the charge.

Sometimes a BMS can turn the charging back on if any cells are detected as going below the full level. However, this is not a sound reason to leave a battery on charge all the time, the safety of disconnection being preferable.
.
 
  • Like
Reactions: Justin Fleming

Justin Fleming

Pedelecer
Mar 6, 2015
31
6
47
Thanks guys. So yes, it does stop charging when it's done so it is ok to leave it on after a full charge.
I don't like leaving things on all the time BUT as it takes many hours to charge after commuting, I can put it on when I go to bed and it should be ready when I get up.
 

flecc

Member
Oct 25, 2006
52,880
30,419
I don't like leaving things on all the time BUT as it takes many hours to charge after commuting, I can put it on when I go to bed and it should be ready when I get up.
While modern lithium batteries are generally very safe, the odd overheating and even fire are not completely unknown.

If you charge overnight while asleep it's good idea to do that in a room with a smoke detector.
.
 
  • Like
Reactions: RobF
D

Deleted member 4366

Guest
Your charger doesn't stop harging when the green light comes on, but it's still OK, even desirable sometimes, to leave it on overnight. Even after the green light comes on, your charger will still hold 42.0V. When your battery reaches 42.0v, in most cases some or all of the bleed resistors that do the balancing will be open to drain down the highest cells. The BMS may or may not switch off the charging MOSFET, while that's happening. It's a little complicated what's going on - basically a lot of switching on and off of trickle charging cells. You can't over-charge your battery because the BMS will prevent it. The longer you leave your battery on charge, the more likely it is to be properly balanced, but you don't have to care about that unless you didn't use your battery for a long time.

This explanation is for your normal Chinese bike. Some, like Bosch, have communication between the battery and the charger, so it becomes a bit more complicated when the charger can ask the battery questions about its charge and balance state.
 
  • Like
Reactions: selrahc1992

flecc

Member
Oct 25, 2006
52,880
30,419
I suppose the same goes for phones etc too though?
Not really. It's the very high capacity of our e-bike batteries that increases the consequences. The amount of energy stored when full gives them the potential to be household bombs.
.
 

AndyBolton

Pedelecer
Feb 9, 2015
37
17
60
I've been led to believe by FreeGo that the THROTTLE is for "cruising" and should never be used alone to climb hills. The manual tells us to first get up to speed on a flat using pedal assist, and THEN engage the throttle if we want to stop pedalling.
 

Blackgold

Finding my (electric) wheels
Jul 14, 2014
23
5
71
When I bought me Tornado I tried a front drive bike an did not like it,it felt likeit was trying to pull me straight on at every corner. I find a bike with rear hub drive,it feels more normal to have the drive at the back.
dont have a throttle and never have need for one.
Its a shame you didnt try a few more bikes,these bikes are all diferent,some of the bikes I tried I just didnt like.
 

RobF

Esteemed Pedelecer
Sep 22, 2012
4,732
2,312
While modern lithium batteries are generally very safe, the odd overheating and even fire are not completely unknown.

If you charge overnight while asleep it's good idea to do that in a room with a smoke detector.
.
I sometimes leave a battery on charge overnight, but out of an abundance of caution I won't leave a battery charging while I am out of the house.
 
  • Like
Reactions: flecc

Kudoscycles

Official Trade Member
Apr 15, 2011
5,566
5,048
www.kudoscycles.com
Whilst all these batteries have a BMS protection sysyem I dont like the idea of leaving even an i-pad charged overnight. There is a lot of energy contained within the battery and as Boeing(Dreamliner fire!) found out it can go wrong.
I advise to all my customers not to leave it charged in the house overnight but I also say that the BMS is there to make it safe.
Your choice.
KudosDave
 

jhruk

Esteemed Pedelecer
May 13, 2009
318
68
I use one of these countdown timers when charging my batteries. I set it to just over the time I expect it to take and then I don't have to worry if I forget to switch it off.

Countdown Timer
 
D

Deleted member 4366

Guest
I've been led to believe by FreeGo that the THROTTLE is for "cruising" and should never be used alone to climb hills. The manual tells us to first get up to speed on a flat using pedal assist, and THEN engage the throttle if we want to stop pedalling.
You can use your throttle how and when you like. The only rule is not to let your motor to slow down much below 8 mph for more than a couple of minutes at full throttle or on the highest level of assist.

Basically, don't let the motor struggle. You can feel it when it is.
 
  • Like
Reactions: AndyBolton

EddieH

Pedelecer
Jan 3, 2015
161
118
68
When I go out on my bike I always put it in the shed on charge and leave it till the next time I use it. Being disabled I cannot keep going downstairs to disconnect it and have had no problems so far.
 

flecc

Member
Oct 25, 2006
52,880
30,419
And you're almost certain not to have any problems Eddie. The BMS will keep the charger from overcharging the battery, and anyway, being in the shed ensures your safety.
.