SeaGeo

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The pack voltage makes no difference in all these comparisons - C-rate, charge curves, etc.
800V charging allows for higher kW (and C rates), but the Hummer and (eventually) the Rivian will utilize 800V charging on 400V packs (or 900V on 450V for the Rivian).
But, as an example, the Rivain charging at 450V and 450A would be a touch over 200 kW. Charging at 900V and 225V yields the same charge (200 kW) and C rate.
Agreed, but I think we're working on different assumptions. The R1 vehicles have large enough batteries that the difference in voltage materially matters compared to a max C rate and charge curve.

I'm working on the assumption that current R1 vehicles will/may stay at 450V if released at 450V and are limited to ~200 kW (maybe 225 at 500amps). But jumping up to 800/900v enables up to ~350 kW. I'm just not convinced by the snipped of RJ said and what's on the website that the *current* gen of vehicles (for example LE) will have that upgrade if it's not available at launch. The vehicles were delayed due to covid, if the hardware is there to enable the patent type switch, I don't really get what would have stopped them from enabling it on the vehicles by now.

I've taken his statement as meaning the next iteration of vehicles or a new model year would have that ability.

Out of curiousity, why reference 900V at 225 amps? Just to show that the kw is the same? There's 900V chargers from EA push out more than 225a, right? Or did I miss something.
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RonS

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KIA EV6 on sale the second half of 2021 will feature a 800V battery pack of 77.8kWh capacity. They claim 10-80% charging in 18 minutes! -- The Kia EV6 | Kia Global Brand Site | Movement that inspires ---and 60 miles in 4.5 minutes. This is with 350kW chargers. I do not know the charging curve. I do not know the charging time with 150kW chargers or even with those 62.5kW chargers that are popping up all over the state of Michigan.
Assuming this information is accurate, it makes me move away from vehicles with 400V battery packs as some of us will road trip in an EV.
Thanks for the tip on the KIA. That’s another vehicle that may meet my needs.
 

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The thing is there's an assumption here of *when they enable* more. There is nothing saying that will actually happen with the R1 series.
That's exactly why I don't care. I'm buying the capability that they are stating will exist at launch - 140 miles in 20 minutes (for at least some portion of the charging curve). If that capability doesn't work for others, they should wait for more definition. I won't judge them - I'll just take their place in line :).
 

SeaGeo

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That's exactly why I don't care. I'm buying the capability that they are stating will exist at launch - 140 miles in 20 minutes (for at least some portion of the charging curve). If that capability doesn't work for others, they should wait for more definition. I won't judge them - I'll just take their place in line :).
I'm (mostly) if the same mind. If they have a flat curve. If it drops off after 20 minutes, I might hold off. Ie, if it went to 150 kw at 25 minutes and 100 me at 30 minutes or something stupid, and took 45 minutes to do 10 to 80%. I'd be floored if that's the case, but they're so tight lipped, who knows However, if they actually have the capability for higher voltage, I'll be quite happy.
 

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Agreed, but I think we're working on different assumptions. The R1 vehicles have large enough batteries that the difference in voltage materially matters compared to a max C rate and charge curve.

I'm working on the assumption that current R1 vehicles will/may stay at 450V if released at 450V and are limited to ~200 kW (maybe 225 at 500amps). But jumping up to 800/900v enables up to ~350 kW. I'm just not convinced by the snipped of RJ said and what's on the website that the *current* gen of vehicles (for example LE) will have that upgrade if it's not available at launch. The vehicles were delayed due to covid, if the hardware is there to enable the patent type switch, I don't really get what would have stopped them from enabling it on the vehicles by now.

I've taken his statement as meaning the next iteration of vehicles or a new model year would have that ability.

Out of curiousity, why reference 900V at 225 amps? Just to show that the kw is the same? There's 900V chargers from EA push out more than 225a, right? Or did I miss something.
Voltage is only one component with C rate. Higher voltages allow current chargers to charge at higher rates - both C and kW.
You could theoretically charge at 300+ kW at 400V and the C rate would be the same as charging at 800V. Either way you are putting energy into the battery pack at the same rate. The higher charging voltage allows for higher charge rates because of the connector/cable limitations.
Rivian is still standing by their statement that an OTA update will enable faster (300+ kW) charging on LE Rivians. This is extremely unlikely to be a change to the pack voltage, but instead enabling the split pack for charging function so that the amperage limits of CCS do not define the upper limit of charging speed.
Once again, to the user it makes no difference what the actual pack voltage is, and whether it is treated as two virtual packs for charging, and one, two or four virtual packs for driving the four motors (thru the inverters that convert the DC battery power to the required AC for the motors - AC is assumed but not confirmed AFAIK)
 

SeaGeo

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Voltage is only one component with C rate. Higher voltages allow current chargers to charge at higher rates - both C and kW.
You could theoretically charge at 300+ kW at 400V and the C rate would be the same as charging at 800V. Either way you are putting energy into the battery pack at the same rate. The higher charging voltage allows for higher charge rates because of the connector/cable limitations.
Rivian is still standing by their statement that an OTA update will enable faster (300+ kW) charging on LE Rivians. This is extremely unlikely to be a change to the pack voltage, but instead enabling the split pack for charging function so that the amperage limits of CCS do not define the upper limit of charging speed.
Once again, to the user it makes no difference what the actual pack voltage is, and whether it is treated as two virtual packs for charging, and one, two or four virtual packs for driving the four motors (thru the inverters that convert the DC battery power to the required AC for the motors - AC is assumed but not confirmed AFAIK)
Voltage is only one component with C rate. Higher voltages allow current chargers to charge at higher rates - both C and kW.
You could theoretically charge at 300+ kW at 400V and the C rate would be the same as charging at 800V. Either way you are putting energy into the battery pack at the same rate. The higher charging voltage allows for higher charge rates because of the connector/cable limitations.
Rivian is still standing by their statement that an OTA update will enable faster (300+ kW) charging on LE Rivians. This is extremely unlikely to be a change to the pack voltage, but instead enabling the split pack for charging function so that the amperage limits of CCS do not define the upper limit of charging speed.
Once again, to the user it makes no difference what the actual pack voltage is, and whether it is treated as two virtual packs for charging, and one, two or four virtual packs for driving the four motors (thru the inverters that convert the DC battery power to the required AC for the motors - AC is assumed but not confirmed AFAIK)
Ah, that's where we are miscommunicating. I was working off the assumption that the 400v battery is hitting the amperage limit of chargers.

I was only using c rate as an upper limit for charging if you have a rate above say ~200 kW with after hitting the amperage limit of current charges and 400/450v.

Maybe I'm just being pessimistic, but I'm not interpreting what they have publicly available as saying that the R1 will be able to go to 300+kW. Their website says the RAN will be able to. They actually do not say that about the R1 vehicles. They just say in the FAW that faster than 140mi/20 min will occur. That could be flattening the curve to average 225 kw for 20 minutes at a 450v system without splitting.
I think both interpretations are reasonable and neither of us knows the answer. That's also where I don't get why they wouldn't release with the split pack idea given the delay they've had if the hardware is baked into this current gen of vehicle.
 

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I'd take GMs claims of 350kW charging with a grain of salt. GM (and many other OEMs) spec the charger type required to achieve their maximum charge rate. As one example, the Kona EV states xx miles in xx minutes on a 100 kW charger. Many people assume this means it will charge at 100 kW when in actuality the max it will get is 77 kW. Since there is no spec for a 77 kW charger, they indicate the type/rating of the charger needed.
GM has started publishing charge rates which actually make sense for three of their new vehicles. Here is what they state so far:

- Hummer SUT with 200KWH battery charges at 800V and 350KW
- Hummer SUV with 165KWH battery charges at 800V and 300KW
- Lyric with 100KWH battery charges at 400V and 190KW

So with the Ultium battery, they are expecting to charge at about a 1.9C rate, but CCS would not support that currently for a 200KWH pack.
 
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Voltage is only one component with C rate. Higher voltages allow current chargers to charge at higher rates - both C and kW.
You could theoretically charge at 300+ kW at 400V and the C rate would be the same as charging at 800V. Either way you are putting energy into the battery pack at the same rate. The higher charging voltage allows for higher charge rates because of the connector/cable limitations.
Rivian is still standing by their statement that an OTA update will enable faster (300+ kW) charging on LE Rivians. This is extremely unlikely to be a change to the pack voltage, but instead enabling the split pack for charging function so that the amperage limits of CCS do not define the upper limit of charging speed.
Once again, to the user it makes no difference what the actual pack voltage is, and whether it is treated as two virtual packs for charging, and one, two or four virtual packs for driving the four motors (thru the inverters that convert the DC battery power to the required AC for the motors - AC is assumed but not confirmed AFAIK)


Going back to their Information from the patent post you made a while back in regards to a configurable battery pack for charging. It sounds like exactly what you are describing and what they filed a patent for, I am now pretty confident from a hardware perspective we are getting the good stuff just have to wait for them to work out the logic of the 900v+ charging.


A configurable battery system according to the present disclosure, including, for example, an electric-vehicle (EV) battery, may be arranged in such a way that at least two battery modules are wired in parallel to achieve a target maximum voltage for an electric load (e.g., 450 V). For DC fast charging, for example, electrical connections to these battery modules may be reconfigured such that the battery modules are wired in series, achieving a high voltage of double the target maximum voltage (e.g., 900 V for a 450 V target maximum voltage). Fast charging (e.g., high voltage charging) may allow both battery modules to be charged at a charging current near a desired current (e.g., a fixed maximum) at the charge inlet. The charge inlet may include any hardware included in the battery charger, the connection between the battery charger and a battery pack, as well any hardware used to conduct charging current in the battery pack, that may carry current during charging. As compared to low voltage charging (e.g., battery modules wired in parallel) with the same total maximum current limitation, the charging current of each battery module would be nominally halved as compared to fast charging.

A configurable battery system allows the techniques of the present disclosure to be applied to an electric vehicle in some embodiments to more fully utilize a battery charger's potential. In some embodiments, it is desirable to achieve a particular charging target. For example, a charging target of 150 kW at 450 V may require a current of 334 A. In this illustrative example, components may need to be sourced to handle up to 400 A continuously to handle the charging. Such components can be difficult to source, expensive, heavier, or difficult to operate. As mentioned above, SAE J1772 is targeting 900 V, 400 A for the maximum output of a typical DC fast charger. If a battery system were able to take advantage of charging at 900 V, the charging target of 150 kW could be achieved at just 167 A, which may allow for more numerous, better quality, or cheaper options for charging components. For example, a current of 167 A may allow different hardware to be used than if the current were nearer to 400 A. In some embodiments, the limitation in charge rate may be the current that the battery module can accept.

In some embodiments, the configurable battery system of the present disclosure reduces, or eliminates, the charge inlet hardware as being the primary limiter in charge rate, and rather makes the battery modules the bottleneck. For example, as cell chemistry improves and battery cells (e.g., of a battery module) are able to accommodate higher currents, the configurable battery system of the present disclosure may be able to supply the necessary power at the higher current. Lowering the charging current in a DC fast charge circuit (e.g., when modules are in series as compared to parallel) may also reduce, or eliminate, the need for cooling to be applied to the charging hardware, as well as reduce the needed size of the DC fast charge cables. For example, in some circumstances, if battery modules are charged in parallel, cables with cross sections of between 95 mm.sup.2 and 120 mm.sup.2 may be required. Such cables may be very large, heavy, stiff, and difficult to package. Also, if components become available at higher voltages such as, for example, at 900V (e.g., for electric vehicles), the battery modules of a battery pack may be able to be configured to charge and operate at 900 V for all conditions.

In view of the foregoing, it is desirable in some embodiments to achieve faster charging, at higher voltages (e.g., 900 V for electric vehicles). One solution to achieve this may be to design the battery load to similarly operate at higher voltages. If off-the-shelf components are not available for operating at higher voltages, then custom components may need to be designed. This can be time consuming and expensive. The configurable battery system of the present disclosure provides an improved and simpler solution that can maximize DC fast charging rates. Such a configurable battery system provides competitive charging rates while still enabling the use of off-the-shelf components. For example, the configurable battery of the present disclosure allows for the use of commercially available 450V components for an electric vehicle (e.g., air conditioning (AC) compressor, positive temperature coefficient (PTC) heater, a drive unit, a DC-DC converted, and on-board charger (OBC)) when either a 450V charging source or a 900 V charging source is used. Additionally, in some embodiments, the configurable battery system of the present disclosure may transition seamlessly into a 900V architecture when the market can support it with competitively priced components.
 

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If you couple the information ^^ with the latest information (April 6, 2021)

http://patft.uspto.gov/netacgi/nph-...&co1=AND&d=PTXT&s1=Rivian&OS=Rivian&RS=Rivian

High voltage laminated power distribution system with integrated fuses

A high voltage distribution system is provided with multiple fuses. The high voltage distribution system includes multiple laminated busbars that are electrically coupled to a battery and to the multiple fuses. Busbars are electrically coupled to the one or more fuses via electrical connections between the busbars and the fuses. The electrical connections can pass through other busbars without having an electrical coupling to the other busbars. An insulating layer may be used between the busbars to prevent overcurrent events. The configuration, size, and position of each busbar is selected based on the electrical requirements of components that are electrically coupled to the busbar and based on the prevention of overcurrent events.

Electric vehicles typically include a plurality of components which each have unique current and/or voltage requirements. For example, an electric vehicle drive unit may require 300 V and a maximum current of 500 A to operate, but a compressor may require 300 V and a maximum current of 40 A to operate. To protect the vehicle's components from damage caused by an electrical short, fuses that can interrupt a short circuit when an overcurrent event occurs are placed in series with a negative or positive path leading to the component. An interrupting current of the fuse is typically selected based on an expected maximum electrical load of the component (e.g., approximately 40 A for the compressor).
It does confirm and sound like they can have variable voltage components based on what is available and still have a High Voltage Backbone Architecture.
 

SeaGeo

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If you couple the information ^^ with the latest information (April 6, 2021)

http://patft.uspto.gov/netacgi/nph-Parser?Sect1=PTO2&Sect2=HITOFF&p=1&u=/netahtml/PTO/search-bool.html&r=5&f=G&l=50&co1=AND&d=PTXT&s1=Rivian&OS=Rivian&RS=Rivian

High voltage laminated power distribution system with integrated fuses

A high voltage distribution system is provided with multiple fuses. The high voltage distribution system includes multiple laminated busbars that are electrically coupled to a battery and to the multiple fuses. Busbars are electrically coupled to the one or more fuses via electrical connections between the busbars and the fuses. The electrical connections can pass through other busbars without having an electrical coupling to the other busbars. An insulating layer may be used between the busbars to prevent overcurrent events. The configuration, size, and position of each busbar is selected based on the electrical requirements of components that are electrically coupled to the busbar and based on the prevention of overcurrent events.



It does confirm and sound like they can have variable voltage components based on what is available and still have a High Voltage Backbone Architecture.
I sincerely hope they have those parents going into the current (hahaha unintended pun) hardware.
 

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I sincerely hope they have those parents going into the current (hahaha unintended pun) hardware.
So if you look at their other patents that were just confirmed 3 days ago (wheels) which are finalized and we know are real Id assume and hope these are too as there is no other patent for what they have in terms of their charging secret sauce.
 

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Not directly related to Rivian network, but EA has announced these new locations for early 2022:

Electrify America plans to build on its momentum by adding charging stations in Hawaii, South Dakota, Wyoming, and Vermont to the network for the first time by early 2022. The new states will bring Electrify America’s presence to 47 U.S. states and the District of Columbia.

I know people on this site should be interested in some of these, especially Wyoming and South Dakota.
 

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Not directly related to Rivian network, but EA has announced these new locations for early 2022:

Electrify America plans to build on its momentum by adding charging stations in Hawaii, South Dakota, Wyoming, and Vermont to the network for the first time by early 2022. The new states will bring Electrify America’s presence to 47 U.S. states and the District of Columbia.

I know people on this site should be interested in some of these, especially Wyoming and South Dakota.
Awesome news! Evanston, WY. P-L-E-A-S-E!!!! 🙏
 

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Awesome news! Evanston, WY. P-L-E-A-S-E!!!! 🙏
Greg,

You know I'm pulling for Evanston and others across Wyoming. The Tetons and Yellowstone areas are sounding better for all of us with the RAN rollout, but let's hope EA fills in more gaps in the Intermountain West and Upper Plains. 🤞🏻
 
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