Hi Oldmanofthenorth, There has been quite a lot of previous threads mentioning 12v battery concerns. As a man from slightly further north than yourself I have had issues with batteries in previous ICE cars. Freezing weather and cold starting being very hard on battery life.
Due to shorter journeys and consequently less HV battery charges I decided to also trickle charge the 12v battery. The battery charged for a full 8 hours (albeit at low current) before the smart charger switched to maintenance mode.
I intend to continue an occasional trickle charge to the 12v battery until longer journeys and more regular HV charges can resume, after travel restrictions are lifted.
I suspect the poor old lead acid battery could become neglected due to our attention being diverted to its high tech brother.
I suspect the main battery is better able to cope with possible low charge state -from leaving factory, to transport and storage time before coming to ourselves.
Anyway regards and enjoy from old man from further north.
PS my wife wants to know where you got my photograph to use as your profile.
Hi Iain,
I also live in Scotland and I am aware of the problems that one has when the 12v battery is not at a full charge. My daily mileage before and after lockdown was always under 20 miles and sometimes even less.
Now unlike many EV Owners I NEVER have a charging regime as I don't see the need. The BMS looks after the HV Batteries health and you can NEVER overcharge the battery (even though the car shows 100% ,it's not, but as far as the user is concerned it is). The BMS will also shut down the car before the battery reaches a dangerously low level.
The BMS will also decide if the car's HV requires an equalizing charge and will instigate that during normal overnight charging, another thing NOT to worry about.
If one is lucky enough to have off road parking and a Home Charger (and I would NEVER expect anyone to have an EV unless they had, as I would find it too inconvenient and expensive to being forced to use public charging at least not whilst the infrastructure is still poor) then just plug it in EVERY time you have finished with the car no matter what the SOC is.
I always do this and I have NEVER had a problem with the 12v battery, besides it is easier plugging in the main charger than mucking around opening bonnets and connecting battery chargers to the 12v battery.
If you do worry about the battery health then DO NOT UNLESS YOU HAVE TO use Rapid Chargers as it is these that cause more damage to EV batteries. This is a bit of a problem if you regularly drive past or close to the cars range but even then the BMS controls the charging and throttles the charger if it thinks the battery needs protecting.
As a last resort one has the warranty to call on, in fact I would be as happy as a pig in mud if my battery pack was changed at say for example 40000 miles. FYI it takes about 45 mins to an hour to change an EV Battery pack. Also nowadays due to PCP,/PCH purchases the car will be long gone before any battery problems materialize.
Any way, just my feelings, I like my driving to be as hassle free as possible, all the best.
Frank