4xe ESS Battery question

Bohunker

Active Member
Joined
Jan 5, 2021
Messages
25
Reaction score
37
Location
Tennessee
Vehicle(s)
4xe Rubicon
I’m planning my upgrades for my new 4xe Rubicon. One of the mods I was considering was a dual battery setup to get rid of the aux ESS battery. Do we know if the 4xe will have a aux ESS battery or will they just use 4xe battery pack for power? Can we tie into the battery pack for our power needs or would use the standard battery like a normal Jeep? Sorry if these are newb questions, but it is my first Jeep and first hybrid vehicle.





Advertisement

 

JLUR4xe

Member
First Name
Justin
Joined
Feb 2, 2021
Messages
14
Reaction score
20
Location
Arkansas
Vehicle(s)
1998 TJ SE, 2021 JLUR 4xe (ordered 2/2)
I would think since the 4xe has the 2.0L etorque with BSG(Built Start Generator) it shouldn't need the AUX battery for ESS. BSG should be responsible for the ESS function and doesn't need the AUX battery. The BSG on the regular etorque uses a separate 48v battery to operate and DC to DC 12v convertor to charge the 12v system. The 4xe will use the main hybrid battery pack.

I still have some questions about exactly how the the DC to DC voltage conversion in the 4xe system will work as the battery pack is 400v. I am assuming they are using the same 48v system for the BSG and I pretty sure the electric motor in the P2 location is running on the full 400v. There also has to be a 12v supply somewhere to charge the 12v system. As for accessing the main battery pack directly that would probably be a bad ideal as it is a 400v high voltage system. The good news is that if I am correct and they didn't put something else in the location of the AUX battery there may be room there if you need the extra 12v capacity.
 

Mike DeSimone

Member
First Name
Mike
Joined
Jan 9, 2021
Messages
9
Reaction score
12
Location
Medford NJ / Lake George NY
Vehicle(s)
2021 Wrangler Unlimited Rubicon 4xe
I wonder if the electric motor in the transmission could be used as the generator instead, leaving everything in 400V or 12V. There would be no need for the 48V system at all, and the 2.0 would have no BSG or traditional alternator.
That's a good thought, and would certainly simplify the powertrain. here's the problem- since there's just one motor to power the wheels while driving as well as provide negative torque on regen, it (the motor-generator) has a clutch on both ends. The problem occurs when the motor-generator would be needed to start the engine at road speed; they would need to go back to a conventional 12v starter. (Clutching the engine to the gen at 2000 RPM would make for a pretty rough start...)And since the 12v system is charged from a 48v converter that would go away they'd have to add a 400-12v converter. Or just go back to using the non-BSG 2.0l engine, but you'd lose the 50 or so HP boost for acceleration and the smooth stop-start.
Clearly I've thought about this way too much. But I love having conversations with folks who think about this stuff. Thanks for the thought starter, and I may be wrong about ALL of it... Maybe it was just marketing's idea.
 

Jeeperz Kreeperz

Well-Known Member
Joined
Jan 15, 2018
Messages
281
Reaction score
259
Location
New Hampshire
Vehicle(s)
2021 JLUR 4xe
I’m planning my upgrades for my new 4xe Rubicon. One of the mods I was considering was a dual battery setup to get rid of the aux ESS battery. Do we know if the 4xe will have a aux ESS battery or will they just use 4xe battery pack for power? Can we tie into the battery pack for our power needs or would use the standard battery like a normal Jeep? Sorry if these are newb questions, but it is my first Jeep and first hybrid vehicle.
I’ve had the same questions. I purchased a Genesis dual battery system for my 2018 3.6L JL, but have yet to install it, as I‘m now considering trading in the 3.6L for the hybrid 4xe. Genesis says their system works with both the 3.6L engine, as well as the 2.0L engine - although I’m not 100% certain as to whether it will work in the 2.0L hybrid without some minor modifications. Tagging @Genesis Offroad here, in case they want to jump in and comment.

As to your question about tying into the EV battery pack for power needs like you would in a dual battery setup, the boys at TFL asked this exact question to Micky Bly, Jeep’s head of global propulsion systems (or some such rocket science title) somewhere in the video below. He gave a somewhat coy answer. I seem to remember he hinted they might be considering something like that in future model years - for whatever that’s worth.
 
Last edited:

AnnDee4444

Well-Known Member
Joined
Jan 14, 2019
Messages
2,482
Reaction score
2,618
Location
Earth
Vehicle(s)
Jeep

Advertisement




Icon Vehicle Dynamics
 



Advertisement
Top