Will Shimano offer wireless recharging for electric components?

Calc wrote:

My mechanical shifters are 'recharged wirelessly' when I eat food.

Isn't it manual recharging when you put food in your mouth or do you always throw food up in the air and catch it?

Personally, I'd rather have wired recharging for bikes as wireless recharging suggests that you either stand there holding the wireless charging pad close to the device or duck tape it in place. With a wire, you just plug it in and can leave the charger sat on the floor or wherever.

It's not quite clear how they envisage this being used, but I can see a few scenarios where it might help:

There is a separate, removable battery pack (or similar) that slots into place on the bike and wirelessly transfers power to the bike's components. Essentially similar to many ebikes, but power transfer is wireless which reduces the need for exposed electrical contacts. This would be useful if you don't have power where your bike is usually stored. 

As many phones now offer wireless charge sharing, if your bike runs out of charge in the middle of nowhere, you could top it up from your phone to get home.

The patent mentions the suggestion that "the non-contact charging devices can be one or two meters away from the bicycle components". If true, this would open the potential for e.g. a "charging zone" within your home/garage - so you neither have to plug the bike in nor hold the wireless charger right next to it. You could simply leave the bike in the general vicinity of the charging device and it would be recharged. Also potentially allows simultaneous charging of several bikes. 

OnYerBike wrote:

It's not quite clear how they envisage this being used, but I can see a few scenarios where it might help:

There is a separate, removable battery pack (or similar) that slots into place on the bike and wirelessly transfers power to the bike's components. Essentially similar to many ebikes, but power transfer is wireless which reduces the need for exposed electrical contacts. This would be useful if you don't have power where your bike is usually stored. 

As many phones now offer wireless charge sharing, if your bike runs out of charge in the middle of nowhere, you could top it up from your phone to get home.

The patent mentions the suggestion that "the non-contact charging devices can be one or two meters away from the bicycle components". If true, this would open the potential for e.g. a "charging zone" within your home/garage - so you neither have to plug the bike in nor hold the wireless charger right next to it. You could simply leave the bike in the general vicinity of the charging device and it would be recharged. Also potentially allows simultaneous charging of several bikes. 

I can see that recharging with your phone might be useful, but am sceptical about your other two uses. An ordinary battery pack can easily be used to charge up bikes and a wireless charging zone sounds useful, but overkill for most people as it'd likely cost more and bike components don't really need charging that often.

hawkinspeter wrote:

a wireless charging zone sounds useful, but overkill for most people as it'd likely cost more and bike components don't really need charging that often.

That's the key I think, even my nine-year-old Di2 battery only needs recharging about once every 1500 miles, which for me is about once every two months, it just wouldn't be worth the expense or the space to have a wireless charging dock in place for when I needed it every eight weeks.

Rendel Harris wrote:

That's the key I think, even my nine-year-old Di2 battery only needs recharging about once every 1500 miles, which for me is about once every two months, it just wouldn't be worth the expense or the space to have a wireless charging dock in place for when I needed it every eight weeks.

yes long enough to make it conveniently easy to forget to charge regularly, best just do it once a month.

Although I have found my Di2 no longer lasts anywhere near that long, I think I hav isolated the issue to the rear derailleur draining power when connected, even while not riding.

wycombewheeler wrote:

Although I have found my Di2 no longer lasts anywhere near that long, I think I hav isolated the issue to the rear derailleur draining power when connected, even while not riding.

Check (or get someone to check) that it's not sitting on the H or L limit screw, thereby never going to sleep properly. A common mistake with setting up Di2 is setting the limit screws before the micro-adjust (as with mechanical you would do the limit screws before cable tension), with Di2, do the micro-adjust first then the limit screws, you can then make sure that it's not touching either at rest.

mark1a wrote:

Check (or get someone to check) that it's not sitting on the H or L limit screw, thereby never going to sleep properly. A common mistake with setting up Di2 is setting the limit screws before the micro-adjust (as with mechanical you would do the limit screws before cable tension), with Di2, do the micro-adjust first then the limit screws, you can then make sure that it's not touching either at rest.

not in top or botom gears, so limit screws unlikely to be a factor. Also I did not have this problem for 3 years, and have a policy of not f***ing with things that work, so the limit screws have not been adjusted to cause a new issue.

wycombewheeler wrote:

yes long enough to make it conveniently easy to forget to charge regularly, best just do it once a month.

Although I have found my Di2 no longer lasts anywhere near that long, I think I hav isolated the issue to the rear derailleur draining power when connected, even while not riding.

It could be the battery failing as they don't last forever. It could also be a dodgy cable, but that's unlikely unless you know that it's been damaged.

hawkinspeter wrote:

wycombewheeler wrote:

yes long enough to make it conveniently easy to forget to charge regularly, best just do it once a month.

Although I have found my Di2 no longer lasts anywhere near that long, I think I hav isolated the issue to the rear derailleur draining power when connected, even while not riding.

It could be the battery failing as they don't last forever. It could also be a dodgy cable, but that's unlikely unless you know that it's been damaged.

I thought it was the battery first, charged it up, disconnected the battery, waited some days, plugged in; still fully charged.

left plugged in; battery drained 20% overnight

unplugged the rear mech held charge again

plugged in the rear mech battery drained again going flat in 2 days

I don't see how a cable could be damaged, UNLESS somehow the battery landed on it, as I found it was no longer secure in the seatpost, but had dropped down the seat tube. But I would expect it to encounter the front mech cable before the rear mech cable.

OnYerBike wrote:

As many phones now offer wireless charge sharing, if your bike runs out of charge in the middle of nowhere, you could top it up from your phone to get home.

seems sensible as the bike battery is probably (electrically) smaller than a phone battery given that it charges much quicker and uses less of my power bank even though it is significantly larger physically

OnYerBike wrote:

The patent mentions the suggestion that "the non-contact charging devices can be one or two meters away from the bicycle components". 

surely this would be very inefficient, I'm not an electrical engineer but it seems to me that the further away you are charging the device, the more energy is lost due to missing the target.

wycombewheeler wrote:

surely this would be very inefficient, I'm not an electrical engineer but it seems to me that the further away you are charging the device, the more energy is lost due to missing the target.

You're right, wireless charging isn't very efficient. It's less of an issue with bike batteries as they're usually smaller and don't require much juice, but the efficiency will drop as the distance increases so ideally you want to position the charging coil right next to the device.