Which battery tender is best for Porsche winter storage?

For your situation, I would suggest looking at some alternatives since the Porsche-branded one is literally just a marked-up rebrand. I've been using the CTEK MXS 5.0 Battery Charger and Maintainer for years on my 991, and it's been rock solid. It has a specific AGM mode which is super important cuz most modern 911s use those batteries and they're picky about charging voltages. If you want something even more high-tech, the NOCO GENIUS10 10-Amp Fully-Automatic Smart Charger is another great option that's usually cheaper than the dealer's price.

Regarding the 12V plug vs the battery, I'd honestly recommend connecting directly to the battery or the dedicated terminals under the hood. I tried the footwell plug at first, but sometimes the car's CAN bus system shuts down that port after 30 minutes to save power, and then your charger stops working without you even knowing! Using a CTEK Comfort Connect Extension Cable makes it way easier to just plug it in under the frunk lid. Just gotta be careful not to pinch the wires when you close it tho. GL with the winter storage!!

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For your situation, I would suggest looking at some alternatives since the Porsche-branded one is literally just a marked-up rebrand. I've been using the CTEK MXS 5.0 Battery Charger and Maintainer for years on my 991, and it's been rock solid. It has a specific AGM mode which is super important cuz most modern 911s use those batteries and they're picky about charging voltages. If you want something even more high-tech, the NOCO GENIUS10 10-Amp Fully-Automatic Smart Charger is another great option that's usually cheaper than the dealer's price.

Regarding the 12V plug vs the battery, I'd honestly recommend connecting directly to the battery or the dedicated terminals under the hood. I tried the footwell plug at first, but sometimes the car's CAN bus system shuts down that port after 30 minutes to save power, and then your charger stops working without you even knowing! Using a CTEK Comfort Connect Extension Cable makes it way easier to just plug it in under the frunk lid. Just gotta be careful not to pinch the wires when you close it tho. GL with the winter storage!!

For your situation, I would suggest looking at some alternatives since the Porsche-branded one is literally just a marked-up rebrand. I've been using the CTEK MXS 5.0 Battery Charger and Maintainer for years on my 991, and it's been rock solid. It has a specific AGM mode which is super important cuz most modern 911s use those batteries and they're picky about charging voltages. If you want something even more high-tech, the NOCO GENIUS10 10-Amp Fully-Automatic Smart Charger is another great option that's usually cheaper than the dealer's price.

Regarding the 12V plug vs the battery, I'd honestly recommend connecting directly to the battery or the dedicated terminals under the hood. I tried the footwell plug at first, but sometimes the car's CAN bus system shuts down that port after 30 minutes to save power, and then your charger stops working without you even knowing! Using a CTEK Comfort Connect Extension Cable makes it way easier to just plug it in under the frunk lid. Just gotta be careful not to pinch the wires when you close it tho. GL with the winter storage!!

Not to disagree with the guys above, but I'd actually suggest a different approach for the connection side of things. I totally agree the Porsche logo is a markup scam, but honestly, I'm wary of the footwell plug.

- Direct battery connection is way more reliable cuz those 12V sockets can sometimes time out.
- It's a MUCH cleaner signal for the electronics... plus no risk of blowing a tiny fuse mid-winter.

Direct to the terminals is definitely the way to go for peace of mind! 👍

I went through this last year when I first stored my Carrera. Honestly, I was sooo paranoid about the lithium battery getting fried or the electronics throwing codes, especially since these cars are literally rolling computers. After doing some deep dives, I realized the Porsche-branded unit is a bit of a markup trap, so I decided to save some cash and went with the NOCO GENIUS10 10-Amp Fully-Automatic Smart Charger.

I was cautious about the 12V footwell plug though because sometimes those ports time out and stop charging after 30 minutes, which is super annoying. Here is how I set mine up for peace of mind:

1. Hardwired it directly to the battery terminals using the eyelets.
2. Ran the quick-connect lead out near the cowl for easy access.
3. Always double-check the 'Force Mode' if the voltage is low.

Basically, the direct connection is safer imo because you avoid any CAN bus sleep mode issues that might kick in with the cigarette lighter. Just be careful with the ground—I always use a chassis ground point instead of the negative terminal to be safe. It’s been rock solid and way cheaper than the dealer option! gl!

> Should I go with the official Porsche Tequipment charger, or is a CTEK model basically the same thing for less?

In my experience, you’re basically paying for the logo with the official Porsche one. CTEK actually makes the chargers for Porsche anyway, so if you buy the brand name version, you're getting the same internals for way less money. I’ve used them for years and they’ve never let me down.

Regarding the 12V plug vs the battery, the footwell is sooo much easier, but some newer 911s have a timeout feature that kills the connection after 30 mins. If that happens, you gotta hardwire it to the battery.

Quick question though—what year is your 911 and does it have the Lithium battery? That lowkey changes everything cuz you need a specific mode so you don't fry the electronics!! gl!

I went through this last year when I first stored my Carrera. Honestly, I was sooo paranoid about the lithium battery getting fried or the electronics throwing codes, especially since these cars are literally rolling computers. After doing some deep dives, I realized the Porsche-branded unit is a bit of a markup trap, so I decided to save some cash and went with the NOCO GENIUS10 10-Amp Fully-Automatic Smart Charger.

I was cautious about the 12V footwell plug though because sometimes those ports time out and stop charging after 30 minutes, which is super annoying. Here is how I set mine up for peace of mind:

1. Hardwired it directly to the battery terminals using the eyelets.
2. Ran the quick-connect lead out near the cowl for easy access.
3. Always double-check the 'Force Mode' if the voltage is low.

Basically, the direct connection is safer imo because you avoid any CAN bus sleep mode issues that might kick in with the cigarette lighter. Just be careful with the ground—I always use a chassis ground point instead of the negative terminal to be safe. It’s been rock solid and way cheaper than the dealer option! gl!