Canadian car, ecu revision '506' bcm.mcm '305'
Just some data points from -10F -23C located in a Koppen Dfb boreal climate zone. [Ab.Ca] It's cold.
Bvo lately is exceptionally high operating in the cold ambient conditions, 182V Bvo, the Maximum possible was observed closely after startup. Nice to have all the bars lit on the dash, but .. The small 'f' ima fan indication is shown on the obdiicc gauge as self heating is attempted. SoC is concomitantly maxed out at 82% - absolute max level noted with forced charging -but not much depth behind SoC for use in reality though. Bam varies ~4-8A. With driving off soon and a pulse or two of ima use, the Bvo will fall slightly, but holding 178-179V is common and back up towards 182V is common at that temp. The ima battery is in self warming mode iirc.
Initially in am, after pm run and left parked in elements, Bte is found around -16C in morning, 'warm' still from last night's ~2-3C, ].
..fwiw: I'm not using Mima but for very sort blips and the battery doesn't want to put out very much on its own for assist until around -9c iirc.
Then the Bvo drops to around 168V; SoC is about 67% and with more use, and Bte rises , often no higher than 10C.
In spite of the apparently higher SoC and Bvo, I still avoid using assist or heavy regen via Mima and anyways, conditions don't warrant lots of torque.
The IMA behaves like this each year and then settles down after the first cold snap. A P1449/1447 code will usually be thrown with first exuberant driving with warmer temperatures in the springtime.
In the cold, if I had a choice I would want a lithium-titanate battery, although if I nurse my NiMH along, it may be alright in the cold for a while, albeit not as usable.
My Canadian ecu got a cold weather revision: "506"
https://docs.google.com/spreadsheets/d/1hSpAMLn7JwvbvxWcM8rR-8z_UvA3UkyuJV6ZSo0Npaw/edit?usp=sharing
Code:
CAN 2000 MT
BCM#1K100-PHM-305
MCM#1K000-PHM-305 Software rev:1C 02 76 00 00
[B]ECM 37820-PHM-506[/B] Software rev:6C 01 11 00 00*
2008 K66 Recall: *new ECM per DC [diagnostic code] Recall. [Tech Service]Bulletin V.5-07 [V.#??TSB]
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On subject of lead batteries, they do seem better for temperature range than lithium. This is one of the reason I'm interested in the Li-titanate type lithium batteries on account of their cold temperature ranges and and excellent charging rate specs.