ebike charging question

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Pale Rider

Legendary Member
I personally have ordered two, 840W/hr batteries for my bike, if Im going to go long distance or in sports mode for hoon-ing off road.

As someone who likes to do 100+ mile rides, albeit at push bike pace, I'm looking forward to seeing your new bike.
 

CXRAndy

Guru
Location
Lincs
As someone who likes to do 100+ mile rides, albeit at push bike pace, I'm looking forward to seeing your new bike.

Hopefully not too far off now, manufacturer asked me about tyre options before completion. Hoping before end of May
 

Drago

Legendary Member
Mine has an intelligent charger, and with each charge charges it to a suitable max capacity that may not actually be 100% 'full'. The electronics manage that far better than me guessing, or using a stopwatch, or relying on the crude indicator to decide when 80% is there. This is how a supposedly puny 317Wh capacity can take me some very respectable mileages - no point having a 400 or 500 Wh battery if a dumb charger isn't utilising that effectively.

The only thing Suntour recommend is not to leave it fully charged for more than a few days, and to totally discharge the battery every 30 or so charge cycles. Beyond that the charger takes care of business very nicely.
 

Pale Rider

Legendary Member
Mine has an intelligent charger, and with each charge charges it to a suitable max capacity that may not actually be 100% 'full'. The electronics manage thar far better than me guessing, or using a stopeatch, or relying on the crude indicator to decide when 80% is there.

The only thing Suntour recommend is not to keave it fully charged for more than a few days, and to totally discharge the battery every 30 or so charge cycles. Beyond that the charger takes care of business.

Bosch is similar, although some of the cheaper Chinese chargers are more crude.

'Cycling' (ho-ho) the battery occasionally is good advice for any gadget which uses rechargeables.

However, it's important not to run it any flatter than the appliance allows.

It can be difficult, nigh on impossible, to resucitate a dead flat battery.

Again, some of the real cheap and nasty ebikes' controllers used to allow the controller to do that, although I think those bikes are now rarely on sale.
 

Legomutton

Senior Member
Health warning, I'm not a battery expert, I have a fair amount of experience with lead-acid leisure batteries but here I am just parroting stuff I have looked up and made an effort to corroborate.

This article is about 10 years old and I can't speak for its accuracy, but it says that Li-ion batteries do not need to be "saturated" or fully cycled like NiCads and NiMH, in fact it's better if they aren't charged to 100%*** (and some chargers actually aim off for that, shutting off at a little less than maximum voltage).

Panasonic 18650 and similar cells are Lithium Nickel Manganese Cobalt Oxide type (NMC) if anybody wants to look them up.

Part of the difficulty here is not knowing for certain what the designed behaviour of a particular charger is.

The summary from the above-linked article:

Simple Guidelines for Charging Lithium-based Batteries
- Turn off the device or disconnect the load on charge to allow the current to drop unhindered during saturation. A parasitic load confuses the charger. [unlikely to apply to an e-bike].
- Charge at a moderate temperature. Do not charge at freezing temperature.
- Lithium-ion does not need to be fully charged; a partial charge is better.
- Not all chargers apply a full topping charge and the battery may not be fully charged when the “ready” signal appears; a 100 percent charge on a fuel gauge may be a lie.
- Discontinue using charger and/or battery if the battery gets excessively warm.

***EDIT It has been pointed out to me that not charging fully could mess up the charge balancing of the cell groups as this commonly takes place after the charge process is otherwise complete. I did say I'm not an expert. Perhaps the statrting point should be to read the manuals, although neither of my Bosch battery or charger manuals is explicit on this point.
- Apply some charge to an empty battery before storing (40–50 percent SoC is ideal)
 
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Drago

Legendary Member
And switch on the charger prior to connecting the battery. This prevents any initial voltage spike from damaging the battery, or the battery's own on board electronics. One only needs to lurk around the ebike forums to see that one.
 
And switch on the charger prior to connecting the battery. This prevents any initial voltage spike from damaging the battery, or the battery's own on board electronics. One only needs to lurk around the ebike forums to see that one.
I saw this and wondered as my wife's Carrera has specific instruction as to the order but my Raleigh (Bosch motor and battery) has no such instruction.
So - being me - I contacted Bosch and asked them. They basically said their systems are better designed and the order in which you plug things in doesn't matter as they are designed to protect from problems. They also said that over charging was not a problem as the system is designed to prevent it.
 

Drago

Legendary Member
Theres at least one Bosch owner on the ebike web forum who has suffered. Im not a member, but i lurk, and I think the most recent one a month or 6 weeks back was a Bosch. Its not surprising they would not admit to even the most remote chance of a potential weakness - nonine will wver admit their product might break down,

Certainly the current Suntour system is a smart charger, and will neither over charge, or charge more than is optimum with respect to battery life. I should think that is also true of Bosch, so they're mpribably being honest about that but.
 
Theres at least one Bosch owner on the ebike web forum who has suffered. Im not a member, but i lurk, and I think the most recent one a month or 6 weeks back was a Bosch. Its not surprising they would not admit to even the most remote chance of a potential weakness - nonine will wver admit their product might break down,

Certainly the current Suntour system is a smart charger, and will neither over charge, or charge more than is optimum with respect to battery life. I should think that is also true of Bosch, so they're mpribably being honest about that but.
That's the problem with Bosch - they are great until they are not great then you have a problem!
I would not have chosen Bosch personally but I got upgraded due to problems so I didn't get to choose!
 

Drago

Legendary Member
I think all the systems have their examples of Friday workmanship out there.

However, some seem to have a reputation massively out of proportion with the reality of the numbers involved, so it takes a lot of quiet ferreting and mental counting when trying to decide what might be genuinely worth avoiding or not.
 

gavroche

Getting old but not past it
Location
North Wales
I recharge mine after every ride and don't ride more than twice a week, weather allowing. I don't own an ebike but was refering to my legs. 😊
 

keithmac

Guru
I have a Dewalt Lithium Ion drill that is 15 years old, 2 batteries that get charged to 100% and both still have great usable life.

I charge my phone to 100%, never had a problem either.

My Lithium Ion Lawnmower and Hedge trimmer, same again charge battery before storage and not had an issue.

My ebike gets run down to 20% then a full charge, for the last 5 or 6 years.
 
Location
Wirral
I have a Dewalt Lithium Ion drill that is 15 years old, 2 batteries that get charged to 100% and both still have great usable life.

I charge my phone to 100%, never had a problem either.

My Lithium Ion Lawnmower and Hedge trimmer, same again charge battery before storage and not had an issue.

My ebike gets run down to 20% then a full charge, for the last 5 or 6 years.
You put them on to charge you have no idea what level the charge controller takes them unless you test the SOC at charge termination?
 

keithmac

Guru
They all have charge indicators, I would assume full means 100%.

I've timed some batteries and worked it back through the charger current supply, definitely taken the maximum rated charge (100%).

Which battery would you like me to take a voltage of after a full charge, take your pick and we'll see what its SOC is.
 
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