Hi. We're new to e bikes. Motorbike enthusiasts normally. The manufacturer recommends discharging the battery completely 3 times before using normally. We rode the bikes a few weeks ago but the battery isn't flat, probably still 2/3 rds full. Is it ok to plug phone via USB to help do it. Or is it ok to leave until better weather to use up the juice? Many thanks

Never heard such rubbish, ignore the advice and just go and ride.

Probably a left over from when batteries were reputed to have a 'memory' effect.

It's not necessary with Li-ion batteries. If not used for a period, best to store them at between 50-80% charge, so yours should be fine.

As Nealh says, best just charge and ride, so each time you go out you start with a full battery, how else are you going to learn what range you actually have with your style/type of riding?

A complete discharge is necessary to gain full capacity after replacing battery packs of some phones - the replacement battery for my OnePlus for example, wouldn't hold what was reported as a "full charge" on the display for long, until it had discharged completely first. I've never heard of complete discharge being recommended for ebike batteries. The one time my 19.2ah ebike battery was showing 10% capacity remaining during a very long ride, it became very warm and the motor made strange grinding noises as it failed to propel the bike. I won't be allowing that to happen again.

Lithium chemistry batteries don't need to what some call 'conditioning', the old Nicad's had memory affect and possibly Nimh but they are history for ebike use.

I have a phylion battery (supplied with Halfords bike) with a 'smart BMS' with an instruction to give a full charge/discharge cycle fully when new so the 'coulomb counter' in the BMS can calibrate and presumably give a more accurate reading on its state of charge/health/usage etc. The BMS has some type of memory and communication system where the supplier can read the usage (and misuse) for warranty purposes. These are extra connections on the battery and are not connected to controller.

https://www.bike-eu.com/products-innovations/nieuws/2020/10/phylion-develops-e-bike-battery-support-platform-10138952

In laptop battery packs (and some phone batteries), there's a chip within each cell which has a low voltage cutoff, and calibrates to the cell - for old laptop battery packs, the advice to gain a little more capacity, is to disable the battery protection in the OS, allowing it to drop to 0%, then charge. I believe the reasoning is that over time, the different cells in the battery packs differ in capability, and the chips inside them hold memory of a charge that the cells may no longer be capable of, causing the BMS to not charge the cells optimally. It's risky - it can kill an ailing cell within the pack, which stops the entire battery pack working, but this has worked for all of my old laptop batteries, if done very rarely - you can gain a few useful %. It can also cause the BMS to report a fault to the motherboard, shutting down all motherboard function - sometimes the motherboards cannot be revived (rare). I don't know if ebike batteries have similar chips in their cells, or if this course of action is at all wise: Losing a £400+ ebike battery is not worth the risk, compared to a relatively cheap laptop battery.

Edited December 24, 20214 yr by guerney

ebike batteries don't use protected cells as that is what the BMS does.

Hi. We're new to e bikes. Motorbike enthusiasts normally. The manufacturer recommends discharging the battery completely 3 times before using normally. We rode the bikes a few weeks ago but the battery isn't flat, probably still 2/3 rds full. Is it ok to plug phone via USB to help do it. Or is it ok to leave until better weather to use up the juice? Many thanks

Can you post the link to where the manufacturer states their battery advice?

Can you post the link to where the manufacturer states their battery advice?

 

This is stated in my Gazelle e-bike manual

 

"On acquiring a new battery we recommend running it completely flat and then fully charging it again three times. Once this has been done it cannot do any harm to charge your battery when its remaining charge is 40% for instance, since the battery actually switches itself off automatically. Thereafter we recommend fully discharging the battery again once every three months."

 

I haven't fully discharged the battery in 5 years of use and there is no noticeable degradation yet.

This is stated in my Gazelle e-bike manual

 

"On acquiring a new battery we recommend running it completely flat and then fully charging it again three times. Once this has been done it cannot do any harm to charge your battery when its remaining charge is 40% for instance, since the battery actually switches itself off automatically. Thereafter we recommend fully discharging the battery again once every three months."

 

I haven't fully discharged the battery in 5 years of use and there is no noticeable degradation yet.

 

I've heard of that being recommended for ebike batteries which have been in storage at a very low charge for a long time. I wouldn't do it.

Can you post the link to where the manufacturer states their battery advice?

 

Their website says "In practice, the battery of an ebike lasts a few years. " and then posts a video on how to look after the battery

 

Their website says "In practice, the battery of an ebike lasts a few years. " and then posts a video on how to look after the battery

 

 

Rude #3 in the video is to charge briefly to 30% once a month if storing - don't BMSs only balance cells when you do a full charge? The video says to "Lightly grease" battery contacts - I use a bit of 99% isopropyl to keep them clean - anyone use silicone grease?