What Does Tesla’s Battery Day Mean for eMTBs?

In entrance of an viewers sitting in Tesla vehicles and tons of of hundreds watching on-line, Musk introduced that new battery applied sciences that will imply his electrical automobiles will probably be extra highly effective, longer lasting, and cheaper. What this boils all the way down to is Tesla with the ability to promote a full electrical automobile for $25,000 USD inside 3 years.

It is spectacular stuff, however will we ever see this expertise in eMTBs, and what is going to it imply for his or her improvement? First, let’s check out the batteries that we use now.

What’s inside an eMTB battery?

In the meanwhile most eMTB batteries are 18650 Lithium-ion (Li-ion). Li-ion batteries had been first developed in 1985 they usually have been the principle driving power behind electrical car improvement as they’re rechargeable and you will get a number of energy from them with out them taking on an excessive amount of house.

The 18650 half refers back to the cells throughout the battery pack. Every battery is packed filled with particular person cells that measure 18mm x 65mm, roughly the dimensions of your finger. These are welded collectively in packs which can be related in parallel. If you happen to take off the plastic shell, it mainly it seems a bit like a bunch of AA batteries all joined collectively.

What goes on contained in the battery is not that vital, however there’s one vital quantity with batteries – watt-hours. This, such as you would possibly anticipate, is a measure what number of watts may be delivered in an hour. So for instance, a 250 watt-hour battery might drive a 250 watt motor on full energy for one hour whereas a 500 watt-hour battery might drive it for two. Most e-bike batteries sit between 300 and 550 watt-hours. The golden bullet with batteries is getting as many watt-hours as attainable, however in case you simply hold including cells you may begin including weight and quantity.

Tesla would not at the moment use 18650 cells, although; it now makes use of the 21700 customary with cells measuring 21mm by 70mm. Tesla developed this cell with Panasonic in 2017 and its bigger quantity means it may be filled with extra anodes and cathodes so can maintain extra vitality. Tesla additionally claims it has an extended lifespan because it needs to be charged much less.

Now we have not too long ago began to see these cells come into eMTBs with Specialized’s Turbo Levo Kenevo being the one we’ve coated essentially the most on Pinkbike. This bike has a large 700Wh battery, making it one of many largest you will get on an eMTB right this moment.

Tesla hasn’t stopped 21700 although, and its announcement on Tuesday is the following evolution of its cell expertise

How is Tesla’s New Battery Completely different?

The brand new Tesla battery has gone up in dimension once more, this time much more considerably to 4680 or 46mm x 80mm. Nevertheless, the true innovation comes from what’s contained in the can. Each 18650 and 21700 customary cells use 2 tabs related to skinny bits of copper and aluminum foil to attach the workings of the battery to the skin world. Not solely are these tabs sophisticated to fabricate however additionally they take up house contained in the battery and cut back effectivity as the present should journey the complete size of the electrode to succeed in every tab.

Tesla’s new design removes these tabs and as a substitute makes use of a “shingled spiral” design to gather the present which reduces inner resistance, reduces price and simplifies manufacturing. Musk mentioned: “The gap the electron has to journey is way much less. So that you even have a shorter path size in a big, tabless cell, then you might have in a smaller cell with tabs. So although the cell is larger, it really has a greater power-to-weight ratio.”
In line with Drew Baglino, the senior vp of powertrain and engineering at Tesla, the improvements increase the vitality by 5 instances, the ability by six instances, and the vary of a automobile utilizing these batteries by 16 %. It is price saying we do not know what the baseline for these numbers are as no actual figures are given however we assume its in relation to the 21700.

Will we ever see this on eMTBs?

The benefits for eMTBs of a extra highly effective battery are clear. You’ll be able to both ship the identical energy in a smaller, lighter bundle, subsequently making the bike deal with and look extra like a conventional mountain bike, or you may hold the battery the identical dimension and increase the vary of the bike.

As spectacular as Musk’s claims had been, there was one downside. Whereas the cells are apparently at the moment in testing, a bodily one wasn’t proven and it’ll apparently be one other three years earlier than the expertise is launched. Do not anticipate to see eMTBs utilizing them immediately both. It took roughly 2 years for the 21700 tech to trickle down from Tesla Mannequin 3 vehicles to the Specialised Kenevo, so you may in all probability anticipate tabless batteries to be the identical, if it even occurs in any respect.

There are additionally causes that bike producers are at the moment happy with the 18650 system and do not see any purpose to alter. There may be nonetheless loads of innovation on this dimension of cell with Bosch unveiling its 625Wh Powertube battery final 12 months, providing an enormous vary regardless of the smaller cell dimension. The internals of those cells are nonetheless being perfected too with engineers experimenting with totally different cathode and anode supplies to spice up capability.

One of many different huge issues of accelerating the quantity of a cell is that it makes it tougher for warmth to flee. If a battery will get too sizzling it has to function at diminished energy or threat damaging itself completely. E-MTBs are sometimes out within the solar all day so the higher warmth administration of an 18650 cell might result in higher efficiency over an extended time frame.

Lastly, as with all issues, price will certainly be an element. 18650 cells are nicely confirmed expertise, have now been refined for biking functions and are extensively produced by quite a few competing manufacturers. New expertise isn’t low cost, particularly in its infancy and whereas Musk is concentrating on a $25,000 USD electrical automobile, we doubt he’ll let that aggressive benefit go simply.

So, will eMTB batteries get smaller, lighter, cheaper and extra highly effective? Nearly definitely. Will that be due to Elon Musk? Most likely not for some time no less than.