Flounce

hi

I'm planning for a 400km brevet, and hopefully a 600km several weeks after that.

I will need an external battery pack for my garmin 510.

What should I get?

I found this Garmin model # on amazon: 010-10644-02

Are there other brands/models you would recommend over the official Garmin external battery pack?

Thanks

kingston 

Any external battery pack will work. Just plug it in at the controls. I prefer the etrex20 for randonneuring so I don't have that problem.

gif4445

I've used a Go Puck ( https://gopuck.com/products/3x )in my limited time in randonneuring and it worked well. It's also available in a 6x model (twice what I have). I would qualify this by saying 360 km is the farthest I have gone and I did not use the trip planning function of my Garmin edge touring plus. I had plenty of batter left in the Go Puck however. As I look to go further, I may have to tweek this of course. Dyno, upgrade of the Go Puck or even a regular battery powered charging source where replacement batteries purchased along the way, are possibilities. I think it makes a difference where you are going and the services available. If you are able to plug in at controls, post offices, food stops etc., it obviously helps.

Flounce

Just some follow up.

After looking at my options, I decided to get the gomadic device that accepts 4 AA batteries and charges your garmin. There is a small weight penalty compared to a standard external battery pack, but the ability to buy AA batteries at a convenience or gas station trumps the small weight penalty.

My handlebar mounted Garmin allows me to plug in a device while riding, and I"ve read that it is far more efficient to start the ride with the battery plugged in (and run off the battery while preserving the charge on the garmin internal batery) rather than recharging the Garmin after it has run low.

That is what I'll be experimenting with.

thanks all.

gif4445

Let us know how it works for you. Good luck!!

noglider 

The latest word on lithium batteries is that they don't need to be discharged to be used well and in fact prefer not to be. So I think it's a good plan to start out with the external battery connected. I don't know if it's more power efficient this way, but it's likely to be good for the long-term life of the Garmin's lithium battery.

joewein

From an efficiency point of view, that is true. When you start with both batteries (internal and external) fully charged, first running off the external battery and keeping the internal battery fully charged depletes the external battery less than first running down the internal battery and then recharging it off the external battery. The latter case will discharge the external battery more because each charge and discharge cycle has voltage conversion losses. Running off the external pack minimizes them.

Having said that, you should never keep Li ion batteries 100% charged for long periods of time. The healthiest charge state for long term storage is around 50%.

Not being able to charge the precursor, the Garmin 500 with a regular USB cable while recording was a major handicap. There was really no excuse for that. I'm glad the 510 seems to work much better in that regard.

Flamme Rouge

I've been using an Anker PowerCore external battery with my 820 ($15 on Amazon). It fits in small bag that sits on my top tube. I start with the charger connected as noted above. Haven't figured out what to do when raining, however.

Carbonfiberboy 

I unplug mine in the rain. OTOH I don't intentionally ride long distances in the rain anymore. My 800 will run ~10 hours on its internal which stays full while it's connected to the external battery. If there's going to be more continuous rain than that, I'm either staying home or getting off the course somehow. Of course I'll always have my wired odometer and a printed cue sheet in a waterproof holder, so theoretically I could fall back on that. I was never fond of trying to read a cue sheet in the dark and rain even before my eyes got bad.