05:01 25-07-2026
Rivian R2 and its 12-volt battery: a $256 part, service-only swaps and a tow if it dies
A Rivian Forums member found the lead-acid pack under the rear seat. Rivian wants replacements done in-house, and a flat 12-volt battery can leave the SUV locked, dark and waiting for a flatbed.
The more affordable Rivian R2 arrives with the same detail that has been fraying nerves among R1S and R1T owners: a separate 12-volt lead-acid battery. Photos posted by a Rivian Forums member show it sitting under the rear seat — lifting the cushion is easy enough, while pulling the battery out looks far more involved. It appears to be the same format used in the R1, although Rivian has not confirmed a matching supplier or part number. No widespread low-voltage failures have been reported on the R2 so far.
The official guide spells out what a flat battery means in practice. The R2 can stop responding to the key fob, refuse to open the doors and trunks, and leave the lights and displays dead. The jump-start harness hides behind the square tow-eye door on the left side of the rear bumper. If power cannot be restored, the SUV has to go on a flatbed.
The catch is not the presence of an ordinary battery but the dependence on a proprietary part. Rivian recommends having it replaced at its own service centres and warns that damage caused by an incompatible battery is not covered by warranty. R1 owners have found the job pricey: a year ago the battery alone cost around $256, and labour could double the bill. The factory warranty on the low-voltage battery runs three years or 36,000 miles — after that the cost falls on the owner, and a trivial piece of maintenance turns out to be harder and dearer than fitting a standard-size unit from any parts shop.
R1 owners have reported sudden discharges and repeat replacements, and Rivian itself warns that once a low-voltage alert appears the battery may need replacing within hours. That record still cannot be transferred to the R2 directly. The company says it reworked the high- and low-voltage architecture on the new model: sleep-mode draw is down and the mini DC/DC converter is larger, so minor background loads are handled by the traction pack while the 12-volt battery cycles less often and should last longer.
Early buyers have already swallowed one hardware compromise — the first Rivian R2 units ship without lidar. A repairability question now sits next to it. Until failure statistics exist, the 12-volt battery is a reasonable service risk rather than a proven defect of the R2.