i3 with 57kWh battery

[i3Houston]

Well no need to replace full battery pack but maybe like model 3 mid range(battery pack with just 25%fewer cells or modules) , that way weight stays the same but the range goes up.

A Tesla battery pack contains thousands of small battery cells unlike an i3's battery pack that contains only 96 large battery cells connected in series. If 25% of an i3's cells were eliminated, the output voltage of the pack would drop by 25% which would not work with the motor and charging electronics.

Some have suggested that the space used by the REx engine could hold additional battery cells, but this would not work because the output voltage would be too high. BMW's choice to use large-format battery cells in a single series-connected string simplifies pack construction and likely minimizes cost but eliminates the possibility of increasing or decreasing battery pack capacity by merely adding or removing cells. Instead, we have seen the capacity of an i3's battery pack increase only when higher capacity battery cells of the identical dimensions have become available (e.g., 60 Ah -> 94 Ah -> 120 Ah).

Tesla battery packs conceptually contain strings of 96 series-connected battery cells like an i3 but with the multiple strings connected in parallel, so the output voltage is similar to an i3's battery pack. To vary the battery pack capacity, Tesla needs only to add or remove some of the 96-cell strings. Doing so maintains the same output voltage which the motor and charging electronics require. A battery pack containing thousands of small cells certainly makes pack construction more complex and likely more expensive, but it does allow packs of various capacities to be built using the same battery cells.

Thanks!

 

[alohart]

The article compared the 2014 BMW i3 REx (60Ah) to the 2017 i3 REx (94Ah)

The additional weight of the 2017 U.S. i3 compared with the 2014 U.S. i3 isn't all due to a heavier battery pack. Part of the additional weight is likely due to equipment that was standard on the 2017 U.S. i3 but optional on the 2014 U.S. i3 like the DC fast charging port and electronics, front seat and battery pack heaters, and maybe other equipment.

I recall that the curb weight of the 2014 U.K. BEV was only ~50 kg (110 lb) less than the 2017 U.K. BEV. Some equipment that was standard in base U.S. i3's was optional in base U.K. i3's, so I think the weight difference in U.K. i3's was likely due almost completely to the battery pack weight difference. However, it's difficult to know for certain because curb weights can be defined differently in different markets and maybe even in different model years.

 

[Anonymous]

I think the weight difference in U.K. i3's was likely due almost completely to the battery pack weight difference. However, it's difficult to know for certain because curb weights can be defined differently in different markets and maybe even in different model years.

Very true - found this gem, where weight of driver and luggage can be included :roll:

Common car kerb weight measurements. Weight of the car with all fluids necessary for operation, including a 90% full fuel tank. The EU kerb weight adds a further 75kg (165 lbs) to the (above) DIN weight to imitate a driver and luggage. There's no fixed standard for a dry weight measurement, it's up for interpretation.
https://www.evo.co.uk/features/21040/what-is-kerb-weight-and-how-much-does-your-car-weigh

 

[Anonymous]

We may need to rely on 3rd-party's rather than BMW for higher capacity battery upgrades (if the market will support). Like this "proof of concept" battery developed for the i3, with a range of 400 plus miles.

https://insideevs.com/bmw-i3-435-miles-per-charge/

 

[i3Houston]

Thats an overkill for my needs! Hopefully 3rd party vendors will offer 40,60 or 80 kWhr packs.

 

[Atv]

I think it is just a matter of time before 3rd parties start to offer options, especially as BEV become more popular and there is a decent population of them. More concerns with the software—what if manufacturers take a page from HP and only allow you to run “authorized” battery packs like HP did with ink cartridges?

 

[CharonPDX]

I think it is just a matter of time before 3rd parties start to offer options, especially as BEV become more popular and there is a decent population of them. More concerns with the software—what if manufacturers take a page from HP and only allow you to run “authorized” battery packs like HP did with ink cartridges?

Absolutely. There are already plenty of places that will swap out/rebuild Prius batteries with higher capacity cells. And there are a few places that will rebuild a Leaf battery pack. I imagine it's only a matter of time before we see upgrades available in addition to just rebuilds.

 

[gt1]

I think it is just a matter of time before 3rd parties start to offer options, especially as BEV become more popular and there is a decent population of them. More concerns with the software—what if manufacturers take a page from HP and only allow you to run “authorized” battery packs like HP did with ink cartridges?

This is quite possible and there are multiple ways to disable the aftermarket components. Tesla remotely bricks their car after accidents. The "rebuildable salvage" title means nothing with Tesla- they will not allow such cars to operate.

 

[JohnKelly]

I think it is just a matter of time before 3rd parties start to offer options, especially as BEV become more popular and there is a decent population of them. More concerns with the software—what if manufacturers take a page from HP and only allow you to run “authorized” battery packs like HP did with ink cartridges?

This is quite possible and there are multiple ways to disable the aftermarket components. Tesla remotely bricks their car after accidents. The "rebuildable salvage" title means nothing with Tesla- they will not allow such cars to operate.

There is a youtube video (somewhere) of a guy who has a workaround of some sort for rebuilding Teslas after wrecks. Very clever dude.

Edit: Here it is: https://www.youtube.com/watch?v=NuAMczraBIM

 

[i3Houston]

There should pack like this available with higher capacity so by upgrading existing modules with newer ones should restore/increase the range, right?

https://www.ebay.com/i/222714525671?chn=ps

 

[Atv]

It is reasonable to assume if the pack is the same size, it should work, but a larger pack might require some programming, or the charging module?

 

[i3Houston]

Thought that the Pack dimensions and voltage is the same between older and 2019 longer range i3.

 

[alohart]

Thought that the Pack dimensions and voltage is the same between older and 2019 longer range i3.

They are, but the energy content (i.e., capacities) of the battery packs differ. The battery management system (BMS) would likely need to be set to the nominal capacity so that it would be able to manage charging and discharging appropriately. The BMS does adjust its battery pack capacity setting based on battery pack degradation over time, but an initial capacity probably needs to be set to very near the actual capacity.

 

[alohart]

It is reasonable to assume if the pack is the same size, it should work, but a larger pack might require some programming, or the charging module?

It should work. However, I would think that the battery management system would need to have the nominal battery pack capacity set.

The charging power hasn't changed since the i3 was introduced except in Europe and maybe other markets where 3-phase 11 kW charging was added when the 94 Ah battery pack was introduced. I don't see any reason why the charging module would need to be changed.

 

[i3marc]

My 2014 is still holding up charge even after the brutal punishment I did to it lately (see my post on my 800 miles each way trip). Charging to 100% almost on each leg.

So looks like I am stuck with it for the time being. I am back to 100 miles of range doing 55 on the freeway and 120 if a mixture of slow and fast traffic on eco pro+ which is always what I use 99% of the time.

I am at 68k miles. Last 3k were in the last 3 weeks as I drove 800 miles north, 800 miles over there and back 800 miles, in addition to 500-600 miles in San Diego.

North of Chico my range was 60 due to the temperature.