Best battery design?

[Kangr]

I like a easily removable battery. The trend of putting a external battery inside the frame also works well as i think it means spare battery's are easier to come by and cheaper. But most of all it has to be easily removable, this was the worst thing about the pivot shuttle. it had a removable battery but the process to get the battery out was such a pain that it was easier to leave it in the frame.

 

[Bomble]

External battery works for me. I wish they would bring out a lightweight, maybe 250w spare to extend the range though, would be perfect then.

 

[JoshDwnHll]

I found when comparing my haibike to a levo that my bike felt more rigid and i put that down to the external battery. Also i m hopeful that they will become really efficient and bring out a 800wh batgery the same size as the one i have

 

[Tamas]

I found when comparing my haibike to a levo that my bike felt more rigid and i put that down to the external battery. Also i m hopeful that they will become really efficient and bring out a 800wh batgery the same size as the one i have

Don't hold your breath on the same size 800Wh battery it's not coming any time soon and not with the current battery technology.

 

[JoshDwnHll]

Haha i wouldnt be surprised of that technology already exists tbh i know that there is a 650wh capacity that is inside the standard bosch 500wh battery case so anything is possible.

 

[Tamas]

Haha i wouldnt be surprised of that technology already exists tbh i know that there is a 650wh capacity that is inside the standard bosch 500wh battery case so anything is possible.

Existing and commercially feasible are two different things. With current technology more capacity comes with a bigger size (weight) so a 650Wh might be squeezed into a 500Wh casing but it is ~30% heavier. New 22700 cells might be the new standard in the coming years (Tesla is using them) and will replace the current 18650 cells but the size and weight won't be changed significantly. The bigger cells will allow faster charging which will be the next step I think.

An interesting article on the subject:

E-MTB Battery Revolution? A realistic Assessment of the Situation | E-MOUNTAINBIKE Magazine

 

[Kernow]

External battery works for me. I wish they would bring out a lightweight, maybe 250w spare to extend the range though, would be perfect then.

I like that idea but it’s got to plug in to the existing battery somehow , it’s no good carrying a small battery if you then end up carrying the big one when it’s empty .
If only there was some kind of all purpose adapter that allowed you to plug in a battery of your choice , perhaps utilise a power tool battery as a top up as they seem to be the best value for power output . No idea how much something like a 5ah Dewalt battery would add to an ebike battery but it’s surely not that difficult ?

 

[bissona]

I like that idea but it’s got to plug in to the existing battery somehow , it’s no good carrying a small battery if you then end up carrying the big one when it’s empty .
If only there was some kind of all purpose adapter that allowed you to plug in a battery of your choice , perhaps utilise a power tool battery as a top up as they seem to be the best value for power output . No idea how much something like a 5ah Dewalt battery would add to an ebike battery but it’s surely not that difficult ?

The RoPD connector used by Specialized and Focus (and others) is hot-swappable, and has data connectors, so could work to tag on extra power in different sizes, but the batteries need to be coded to the motor (at least for Shimano) in order for them to be 'allowed' to provide power. I assume this a safeguard against the proliferation of cheap & nasty power-packs but that's guesswork on my behalf.

 

[Wiltshire Warrior]

no such thing as a stealthy e bike - either the noise or the speed will give it away.

 

[steve_sordy]

Who else apart from Speccy and Focus use the RoPD magnetic connectors?

 

[MattyB]

Haha i wouldnt be surprised of that technology already exists tbh i know that there is a 650wh capacity that is inside the standard bosch 500wh battery case so anything is possible.

Existing and commercially feasible are two different things. With current technology more capacity comes with a bigger size (weight) so a 650Wh might be squeezed into a 500Wh casing but it is ~30% heavier. New 22700 cells might be the new standard in the coming years (Tesla is using them) and will replace the current 18650 cells but the size and weight won't be changed significantly. The bigger cells will allow faster charging which will be the next step I think.

An interesting article on the subject:

E-MTB Battery Revolution? A realistic Assessment of the Situation | E-MOUNTAINBIKE Magazine

I suspect what Josh may have been suggesting is that the absolute max capacity of the battery may be higher than 500Wh, but because the BMS optimises for maximum cycle life the usable capaicty is lower. This is pretty standard in consumer goods like computers and mobile phones. As an example the lipos I use in RC are generally considered to have a max voltage of 4.2V/cell and a minimum of 3V/cell, but you can increase the cycle life out of that pack by charging only to say 4-4.1V/cell, and discharging to 3.5-3.7V/cell. You can't fly for so long then though!

 

[SquireRides]

The uptake of 22700 type cells (which are essentially just a different way to pack the same old Li-ion parts together) should mean a few % better energy density for eMTBs over the next 2-3 years. That should be enough, with other manufacturing improvements from Bosch, for a 650Wh battery option that drops in to today's 500Wh external mount.

While there's lots of battery tech coming, you have to look at what new battery types are actually going in to volume production now. Solid state Li-ion and a few other variations on Li-ion should hit volume around 2021/22. If they don't all get snaffled by automotive, then the likes of Bosch can start the process of taking them to the eMTB market. That in itself might require them to develop new BMS and new battery units to house the new cells. Another 18-24 months perhaps?

After all that - by about 2023/24 - we may see new cell technology delivering 30-50% better battery density for eMTBs.

Summary - Enjoy what you have today....

 

[100 Cols]

Who else apart from Speccy and Focus use the RoPD magnetic connectors?

Lapierre Overvolt Shimano series.

 

[100 Cols]

The RoPD connector used by Specialized and Focus (and others) is hot-swappable, and has data connectors, so could work to tag on extra power in different sizes, but the batteries need to be coded to the motor (at least for Shimano) in order for them to be 'allowed' to provide power. I assume this a safeguard against the proliferation of cheap & nasty power-packs but that's guesswork on my behalf.

However, I simply bought a second battery for my Shimano motor equipped Overvolt, absolutely without any coding work in the shop. Bike never complained about unknown battery. It just works.

 

[Mabman]

"The uptake of 22700 type cells"

I have seen this reference a few times here. Actually the new cells depending on the manufacurer are 20700 or 21700 of which the latter is the most popular due to Tesla adopting that format, although they call them 2170's, and most likely to end up the new standard replacing 18650's in the next few years.

Their higher density allows for a higher mah rating so it takes less actual cells to make the same amount of wh's so using them in a similar size format will yield a higher wh rating. But because they are slightly bigger going forward it will be up to the manufacturers to supply batteries that are retrofittable to replace the stock 18650 ones. Otherwise they will just do what the bike industry always does and dangle the new tech out there and make you buy a new bike to get with the program.....

 

[Kernow]

Interesting but way beyond my techy understanding . Coding shimano battery , never heard of that , shimano battery fits any shimano bike swap all you like

 

[bissona]

However, I simply bought a second battery for my Shimano motor equipped Overvolt, absolutely without any coding work in the shop. Bike never complained about unknown battery. It just works.

Good to know, very interested in a Lapierre next time around.

Coding shimano battery , never heard of that , shimano battery fits any shimano bike swap all you like

We watched the dealer plug a new Focus integrated battery into the motor but the bike wouldn't even turn on. Plugged into a PCE1 box, applied eTube firmware updates and all was fine. He said that was down to the battery being a 3rd party Derby unit, not required for original Shimano batteries.

 

[Mabman]

"Coding shimano battery , never heard of that , shimano battery fits any shimano bike swap all you like"

That is true but a Bosch battery won't work with a Shimano motor and a BMZ Brose battery won't talk to either etc, etc. The proprietary software used by big companies these days is all about keeping their business to themselves which locks the consumer into using only their products and service centers.

The same concept on a larger scale: John Deere Just Swindled Farmers out of Their Right to Repair

 

[Kangr]

Interesting but way beyond my techy understanding . Coding shimano battery , never heard of that , shimano battery fits any shimano bike swap all you like

Some come with different fittings. We had a pivot shuttle and a orbea wildfs in. The orbea would not switch on. Suspecting the battery we took the one from the pivot to put in the orbea to test, only to find that they had different fittings. both were external shimano batterys that mount inside the frame, and on first glance look identical. Now we thought it looked like you could take the fitting (the bit that plugs into the bike) off and swap them over but we didnt want to risk trying.
Also the lapierre uses the snake battery so this wont fit a standard shimano either.