Ok now to cheer you all up, do you charge batteries up with the battery switch on or off.If anyone could advise when they stop laughing would be appreciated.
Battery charging
- Thread starter cyclenut1952
- Start date
Ok now to cheer you all up, do you charge batteries up with the battery switch on or off.If anyone could advise when they stop laughing would be appreciated.
I actually read the manualformy wife's ebike a few days ago - which is unusual
Turns out I am supposed to have it switched on.
My own ebike doesn't have a switch on the battery so the question doesn't arise - on my old ebike the manual said to have it switched off
So - I guess you should read the manual and see.
BTW - mike is a Bosch ActiveLine - I suspect it switchs itself on when you start charging it - but Bosch like to keep secrets
Turns out I am supposed to have it switched on.
My own ebike doesn't have a switch on the battery so the question doesn't arise - on my old ebike the manual said to have it switched off
So - I guess you should read the manual and see.
BTW - mike is a Bosch ActiveLine - I suspect it switchs itself on when you start charging it - but Bosch like to keep secrets
Hi Michael, thanks for replying, I did look at my manual but no mention of switch on or off. So I had to ask, as usual I got a positive response, this forum is great. Brian
I suspect that my wife's battery is supposed to be switched on is something to do with having the BMS able to be in control and do 'stuff' - presumably balancing the cells or something
But they don't give that much in the way of detail
I would suspect that if it doesn;t say then it makes no difference - so I would leave it off - and in the meantime try emailing the manufacturer of the motor/battery and ask them
But they don't give that much in the way of detail
I would suspect that if it doesn;t say then it makes no difference - so I would leave it off - and in the meantime try emailing the manufacturer of the motor/battery and ask them
Have a read of https://electricbike.com/forum/forum/knowledge-base/batteries-aa/12542-luna-hardcase-battery-documentation
especially the part concerning Switched pack charging
I don't know why these things are so complicated, it would be much easier if we could just plug the thing in and when the red light goes green its done.
especially the part concerning Switched pack charging
I don't know why these things are so complicated, it would be much easier if we could just plug the thing in and when the red light goes green its done.
Many thanks for replying, crikey that article is going to take some reading ,although plenty of time now.
I have just bought a new X-Go battery for my bike and the instructions for that say have it turned on when charging "to ensure it fully charges." No idea why that is.
The switch is wired via the BMS and turns on the charge/balance circuit.
Most BMS have twin circuits one for discharge and one for charge.
The charge circuit during balance uses bleed resistors to release higher voltage .
Wow, that's really interesting and helpful to know. Thanks
In terms of charging, am I correct that it is best to discharge fairly fully (say 20%) before recharge, to remove the charger as soon as the green light appears and to leave it fully charged for the shortest possible time?
No need to discharge to 20% just for charging unless of course you go for along ride , generally charge the battery once it goes below 80% or so.
When the charger turns green it means it has registered max voltage on one or more of the cell groups but doesn't automatically mean the battery is at full voltage or fully balanced , only a meter reading can tell you the actual voltage.
With a new battery I would charge till green then leave t for half hour before disconnecting, check the voltage and if it reads as it should 42v for a 36v you will then know balance is good and in the future just disconnect the charger when it has gone green.
When it goes green the BMS may be balancing out slight anomalies in cell voltages, even 0.1v is a large voltage difference and can cause issues when voltage lowers.
An indication of a battery out of balance following a green light charge is a voltage reading that appears low. Balancing depends on the BMS and how it is programmed but generally the voltage is above 4.15v per cell group.
Fully charge for the shortest period is good practice, though leaving a battery at too low a voltage can cause issues if it self drains more so when not used for months on end. 40- 70% is a good ball part figure for resting voltage.
When the charger turns green it means it has registered max voltage on one or more of the cell groups but doesn't automatically mean the battery is at full voltage or fully balanced , only a meter reading can tell you the actual voltage.
With a new battery I would charge till green then leave t for half hour before disconnecting, check the voltage and if it reads as it should 42v for a 36v you will then know balance is good and in the future just disconnect the charger when it has gone green.
When it goes green the BMS may be balancing out slight anomalies in cell voltages, even 0.1v is a large voltage difference and can cause issues when voltage lowers.
An indication of a battery out of balance following a green light charge is a voltage reading that appears low. Balancing depends on the BMS and how it is programmed but generally the voltage is above 4.15v per cell group.
Fully charge for the shortest period is good practice, though leaving a battery at too low a voltage can cause issues if it self drains more so when not used for months on end. 40- 70% is a good ball part figure for resting voltage.