Connecting battery tender to battery cables?

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Would there be any issues with connecting a battery tender to the battery cables at the starter and ground as opposed to the battery posts themselves?
 
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If the connections are clean and tight, probably not, but any extra resistance will mess up the measurement of voltage, and hence, charging.
 
No. Just make sure it is a constant hot direct connection.

I used the main connection to a distribution/fuse box underhood on my truck out of convenience (side terminals). My BMW has the battery in the trunk, but I connected the charger leads underhood to the main cables. It has worked great for years.
 
No problem. My 2014 has the battery underneath the passenger seat however there are posts under the hood to hook up cables if needed. I never had to mess with it.
 
No but if that's going to be a pain to get access to, then I'd run wire to make a remote access point where it is more convenient, and for low maintenance level current, I'd consider using a DC barrel jack/plug combo instead of a clamp to post setup.
 
I added length to the two wires on one of these connectors and connected them to the battery posts. I have the connector tucked behind one of the vertical grill supports on the bumper. It's out of sight until I reach in and pull it out. It connects directly to the Battery Minder charger/desulfator I use. After "restoring" a three year old battery that was weak enough to be replaced I started connecting the charger to it any time I wasn't using the car. Now, I just connect it once a week. Nine months later the battery still reads 12.7V and does not drop below 11V when starting the car. The desulfation process is very slow, but I've read about batteries lasting at least double their normal lives by doing this. Some of those anecdotes were from this site.

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Originally Posted by Astro14
If the connections are clean and tight, probably not, but any extra resistance will mess up the measurement of voltage, and hence, charging.


Ouch. So this would definitely be a no go on a car with the battery in the trunk like a P2 Volvo then?
 
I've got the cables on three cars, the 2001 V70, the 2002 V70 and the S600.

All three have the battery in the trunk. I attached the ring connectors to the battery clamps. No resistance. No loss.

I've got to back the car into the driveway to make the connection. But they work great.

I wouldn't connect the ring connectors to the jump points under the hood. I think the Battery Tender directions tell you to connect directly to the battery.
 
Originally Posted by Astro14
I've got the cables on three cars, the 2001 V70, the 2002 V70 and the S600.

All three have the battery in the trunk. I attached the ring connectors to the battery clamps. No resistance. No loss.

I've got to back the car into the driveway to make the connection. But they work great.

I wouldn't connect the ring connectors to the jump points under the hood. I think the Battery Tender directions tell you to connect directly to the battery.


Do you shut the tender wire in the trunk or just go through the battery vent hole?
 
Originally Posted by Astro14
I've got the cables on three cars, the 2001 V70, the 2002 V70 and the S600.

All three have the battery in the trunk. I attached the ring connectors to the battery clamps. No resistance. No loss.

I've got to back the car into the driveway to make the connection. But they work great.

I wouldn't connect the ring connectors to the jump points under the hood. I think the Battery Tender directions tell you to connect directly to the battery.


They generally say to connect the negative to chassis, positive to battery.

As none of these are charging at appreciable rates, the resistive drop is sufficiently low that the conductor length doesnt matter much. One of the reasons to connect to the battery is because it wont work if connected to a switched source. BMW sold a trickly charger that went through the cigarette lighter port - it was a relabeled battery tender!
 
I close the trunk/hatch on the battery tender cable. It's an extension cable, relatively thin gauge, and easily replaceable. No gasket damage from that thin cable.
 
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