New Defender Charging battery via cig lighter?

[991TS]

I tried this on a MY23 defender using a CTEK one having bought all the numerous accessories required (cig adapter and extension lead).

However it seems it hasn’t actually charged the battery as car is flashing low battery warning. Connecting the charger with leads to the battery jump posts under the bonnet has it charging fine

So question is it possible to charge the new defender via the cig lighter? Seems odd not to as it works fine on my other cars

Cheers