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Lithium Battery Upgrade Kimberley Karavan

Lithium Battery Upgrade Kimberley Karavan

SAFIERY UNIVERSITY

LITHIUM BATTERY UPGRADE FOR KIMBERLEY KARAVAN

This article describes the ease of upgrading AGM Batteries to Lithium Batteries and get up to 375Ahr capacity.

Upgrading from 200Ahr AGM to 250Ahr Lithium:

  1. Weight drops from 67kg to 31kg
  2. Usable capacity increases from 50% of 200 Ahr =100Ahrs to 90% of 250 Ahrs = 220Ahrs
  3. Charging ability under solar becomes 27% more efficient
  4. Charging time from Generator reduces significantly.

1. Replacing 2 x Ritar 100 Ahr Batteries with 2 x 125Ahr SAFIERY Lithium

  • This is a straight forward job as the size of each is virtually the same.
  • Before starting, make a note of the serial number of each battery and the position it will be in. We will rename the battery from a long serial number to a name of your choice later.
  • Undo the restaining strap accross both AGM batteries.
  • Undo the terminal conections.
  • Remove the AGM batteries. (last time you will lift 33 kg battery)
  • Keep the washers and use the same cabling
  • Insert the bottom Lithium battery.
  • Insert a foam packer at the top of the bottom battery in the rear as the bottom profile of the Lithium battery is slightly smaller than the top. This keeps the face of the battery square. This packer should be about 25mm thick. Use the packing material around the SAFIERY Lithium battery and cut to suit with a stanley knife.
  • Insert the top battery.
  • Tighten the strap. You may need a 35mm M5 SS bolt for this. Buy from Bunnings, it doesnt need to be a hex head special bolt.
  • Re-connect the cable conections.
  • Thats IT for 250Ahrs.

2. Expand to 375Ahrs

  • The third 125Ahr battery should be placed on its end in vertical position.

  • To hold this in place, an additional stopper is needed on the battery lid or use a stopper at the bottom of the storage box before the turned up vertical edge.

  • This battery will need a new restraining strap. You can use the existing stainless strap at the bottom fixing point to add a flexible “just strap” anchoring it to the same fixing point. On the other sizde of the battery, add a simple saddle. The restraining stap will need to go over the top of the battery and come around and be joined on the front side of the battery. Position the strap locking buckle here.

  • Connect additional inter battery cables with 35mm sq cable going to the battery with just one existing cable (bottom battery on right)

3.  Renaming Batteries

  • One of the nice things with the SAFIERY app is the ability to name the batteries.

  • Enter the passcode on the first display (it isnt 1234) and then enter the new name. We suggest using the battery position. To identify which battery is in which position use the Bluetooth serial number.

  • Connect additional inter battery cables with 35mm sq cable going to the battery with just one existing cable (bottom battery on right)

4. Using the App

Download the app from either the apple store or the google play store:

  • Open the app.

  • You will see 1, 2 or 3 batteries appear on the display.

  • Each battery will have a serial number and a bluetooth communication strength value expressed in dB. It will be a negative number like -65dB.

  • To manage this you will need an advanced battery monitor…. with artificial intelligence.

 

You need to know two important items:

  • State of charge (called SOC)

  • Time to go (called TTG)

Simple Clean Colour Display with high contrast Gorilla Glass.

  • Displays the State of Charge (SOC) as a percent with a coloured circle indicating the battery health (blue for healthy, orange for unhealthy, red for alarm)

  • The “lightning” icon and blue “up-arrow” indicate 100% SOC is expected in 9.5 hours

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Intelligent-DC-DC-Charger

Intelligent-DC-DC-Charger

SAFIERY UNIVERSITY

LITHIUM BATTERIES INTELLIGENT DC to DC CHARGERS

This technical article is designed to give value to the reader through more knowledge of charging Lithium Batteries with a DC to DC Charger.   

Great Charging from Vehicle and Solar

DC to DC Lithium Chargers supply:

  • Up to 25A Charging from the vehicle
  • Work with vehicles that have smart alternators
  • Up to 360W of solar panel power transferred
  • Operate at 96% efficiency.

Recovery of Lithium Batteries after Deep Discharge.

In early 2012, we had installed a well know brand DC to DC charger on 240 Ahrs of Lithium Batteries. After a deep discharge, the customer could not recover the batteries. We had to go out and purchase a very low current constant power supply of 1-2A to recover the batteries. After deep discussion with the battery manufacturers’ engineers, we understood the problem. It was not the batteries, but the DC to DC Charger.

When Lithium batteries have a deep discharge, the voltage will nose dive very fast and very deep. Once below about 8-9V, the BMS in the Lithium Battery will not allow it to be charged at a high charge rate.

Most DC to DC Chargers start up by “sensing the battery voltage”. The Lithium Battery BMS will show maybe 3-4V to the DC Charger. Those DC chargers may them want to thump through a medium or high output current to recover. The Lithium BMS will not allow this for safety reasons. Hey presto: an impasse with no recovery.

PROJECTA solved this problem with the new IDCL 25.

The Projecta team have addressed this in their IDC25L Lithium DC to DC Charger.

When in recovery mode, the charger starts with 2 levels of “soft start”.Soft Start 1 Constant 1.25A if 2V< Battery Voltage <8V

Soft Start 2 Constant 6.25A if 8V< Battery Voltage <10V

Bulk 20A at 9-11Vdc input; 25A at 11-32Vdc input

Hey presto: full Lithium recovery!

Need a Bullet-proof Combination

Deep discharges can occur on a trip. It has happened to me several times.

  • Recovery is vital
  • Recovery has to be bullet-proof with little mucking around.

Charge efficiency

  • PROJECTA IDC25L has a charge efficiency exceeding 94%
  • Typical AGM Batteries are around 75% efficient. But as Lithium is close to 100%, you need a high efficiency charger to match them.

Charging from Solar is full 360W

  • Some DC to DC Chargers have a solar rating that is less than the vehicle rating. But not PROJECTA IDC25L. It is 360W solar power charger!

Compact Design

  • Only 123mm L 122mm W and 40mm high
  • Fits into the engine bay of most 4WD

IP 67 RATING

  • Waterproof and Dustproof to IP 67