I just bought 3 slightly used K2 Group 27 batteries from a friend who is selling his boat. The price was too good to pass up. I have read enough about fires, safety, etc to be concerned, so I want to make sure I get a charger that is meant for these batteries. I park my boat in the garage which Is directly connected to my house. I have read about “lithium profiles” and have been told that I can send my Minn Kota 3 bank battery charger back and have them reprogram it. I have also read it will work at 95% of the optimal levels. That doesn’t seem too bad. Minn Kota’s website says the standard charger will work on the AGM setting. I have heard not to do that long term. I don’t want to spend close to $500 on a 3 bank lithium battery charger. I don’t want to get into a “lithium batteries are too expensive” debate, but I would love some advise from lithium battery users.

Since you went to the expense of purchasing the batteries, why are you hesitant to get all you can out of them? Seems a bit counterproductive. I would want the correct tool for the job.

Is your charger a “Precision” or “Digital”? The Precision chargers will work the same as with other batteries on the AGM setting but the Digital chargers will need to be unplugged once the battery is full. Do not trickle charge a lithium battery.

I have a Minn Kota 330D digital charger. 

Is it possible to purchase the lithium battery charger your friend used for his boat or swap him a standard battery charger?

Most lithium batteries are sold with a charger specific to those batteries as a set. Lithium ion uses a inverter charger set at 14.6V storage and 13.4V float approximately, much higher then a conventional onboard charger.

Tom

 

Tom,

My friend was leaving his 4 back charger in the boat he was selling. I order the chargers today from K2. It won’t be as convenient as the on board, but at least I know it will work and will be safer.

On 2/4/2019 at 7:54 AM, Rodney Smith said:

I have a Minn Kota 330D digital charger. 

The MK 330D digital charger SHOULD NOT be used with lithium batteries. The only case where it would be safe for you and for the batteries would be if you were to manually shut off the charger immediately when the battery is fully charged.

Thanks for the input. I ordered the single chargers from K2. It won’t be as convenient as an on bank charger, but at least I know it will work.

3 hours ago, Rodney Smith said:

Thanks for the input. I ordered the single chargers from K2. It won’t be as convenient as an on bank charger, but at least I know it will work.

Might be able to sell your MK330D and upgrade to an MK Precision Charger. The Precision chargers are capable and frequently used to charge lithium batteries when on the ‘AGM’ setting.