CARS
Date: 06.03.2019

Model: All Models Fitted with an Optional
Lithium Battery Pack

Number: 2019/04

Copy files should be maintained by:
Service Manager

[Text
here].
[Text
here].

Service Reception

Lotus Technicians

Parts Manager

[Next
para
spacing]
TITLE:
[Next
para
spacing]
Importance of lithium battery maintenance and adhering to the stages required for performing the corYours
sincerely
Kind
regards,
(Delete
as as
appropriate)
rect
charging
and /test
procedures.
Yours
sincerely
/ Kind
regards,
(Delete
appropriate)

T +44
(0)1953
[######]
(0)[####
######]
T +44
(0)1953
[######]M +44
M +44
(0)[####
######]

Background
[name]@lotuscars.com
[name]@lotuscars.com
Lithium batteries continue to slowly self-discharge when not in use (such as when the vehicle is in storage), but compared to standard lead-acid type batteries, the rate of discharge will remain reasonably
stable between 13.2V down to 10V, but then will rapidly discharge as the battery voltage falls below 10V.
Although the battery protection voltage device will activate at this time, so isolating the battery from
the vehicle, (refer to Technical Service Bulletin TSB 2018/17) the lithium battery will continue to selfdischarge, but potentially at a more rapid rate than an equivalent lead-acid type battery.



















 


ACTION:
From the time of delivery from the factory and whilst the vehicle is in storage, Lotus recommends:
- The LED status indicator light located on the top of the battery protection device is monitored to
ensure that it remains illuminated. With the batTest Maintain
tery connected or disconnected from the vehi6 6
cle, use the lithium battery tester/charger supplied with the vehicle to perform a ‘Maintenance
7 7
Charge Cycle’.
5
8 8
- Once connected, LED status indicator #6, 7 or
4
3
8 light on the tester/charger will initially flash for
10 seconds as a ‘Pre-Qualification Test’ is being carried out to assess the batteries condition prior to
beginning the ‘Maintenance Charge Cycle’.

 

 
 



- If the LED status indicator #6 light is then constantly illuminated, then this means that the initial nominal battery voltage and condition was satisfactory to begin the ‘Maintenance Charge Cycle’;
But;
- If indicator #6 light is extinguished and indicator #3,4 or 5 lights are illuminated instead, then this
means that the battery charge has dropped below the recommended nominal voltage and that a full
battery recovery/deep charge/retention test cycle (shown as stages 2 - 5 on the following pages),
is in progress to confirm the battery overall condition. During this period the battery IS NOT BEING
CHARGED, DO NOT remove the tester/charger from the battery as this process MAY TAKE MORE
THAN 24 HOURS TO COMPLETE!
The battery is only going through a 'Maintenance Charge Cycle' when LED status indicator #6
light is constantly illuminated and only being 'Charged' when the LED 'Charge' indicator #4 light
is illuminated.
Continued...

CLASS 4

REASON:
It is possible that some lithium batteries have been irreparably damaged because of they have not been
maintained
whilst
the vehicle is in storage or have been diagnosed as irreparably damaged because the
[Name]
– [Title]
[Name]
– [Title]
correct
charging
procedure
has not been carried out.
LOTUS
CARS
LIMITED
LOTUS CARS LIMITED

Bulletin number 2019/03
continued Page 2

CARS

Test Maintain
6 6

1. External power
2. Reverse Polarity Indicator

The following procedure describes the testing and
charge
cycle
stages carried out by the tester/charger
[Text
here].
[Text
here].
in the event that the initial battery charge has fallen
below
acceptable
[Next an
para
spacing]level.

[Next para spacing]

5
3

Test Indicator Lights

7

7

8

8

4

Yours
sincerely
/ Kind
regards,
(Delete
as as
appropriate)
Yours
sincerely
/ Kind
regards,
(Delete
appropriate)
Time period: 10 seconds

Dependent upon the battery condition*, any of test indicator lights #6, 7 or 8 will
Stage 1.
Pre-Qualification flash, testing the: - Battery condition prior to charging
- Ambient temperature acceptable for charging to commence
Test
[Name]
– [Title]

Stage 2.
Safe Low
Voltage
Recovery

This mode will automatically engage option 1 or 2 if the battery is more that 90%
discharged or the voltage is below 12.8V. The red SAVE indicator light #3 will
illuminate and the charge current is adjusted to the battery voltage and ambient
temperature readings taken during the 'Pre-Qualification Test'.

Option 1 (if required) Very Low Voltage Save: A low charging current is applied, the Tester/
Charger will monitor the progress of the battery voltage, increasing the charge rate if the battery voltage rises within an acceptable time period. If the battery voltage does not increase and
rise above 8.8V within 2 hours, charging will stop and the red TEST Indicator light #8 will flash
indicating the battery may be permanently damaged.
Option 2 (Mandatory) Low Voltage Save: if the battery voltage has risen or was originally
above 8.9V (but below 12.8V), a higher charge rate is applied to the battery, again the Tester/
Charger will monitor the progress of the battery voltage and battery condition. If the battery
condition is acceptable the Tester/Charger will start a ‘Charge’ mode within 4 hours. If the battery condition is not acceptable then again, the red TEST Indicator light #8 will flash indicating the battery may be permanently damaged.
Time period: up to 12 hours (cumulative)
If the Tester/Charger determines the battery condition is acceptable after stage 2 has
Stage 3.
concluded, the battery will now begin the charge procedure and the yellow CHARGE
Normal
Indicator light #4 will illuminate. The rate of charge is determined by the ambient air
Charge
temperature, current vehicle charge, battery condition and battery capacity (Ah).
Time period: up to 18 hours (cumulative)
Once the battery voltage reaches 14.3V during ‘Charge’ mode the Tester/Charger will
Stage 4.
begin ‘Optimize’ mode and Indicator light #5 will illuminate. The current control program
Optimize
within the Tester/Charger will apply pulses of current resulting in the battery voltage to
vary and equalize the individual cell charge levels within the battery. If, after this procedure the battery charge level is deemed:
- Acceptable - No further charging, the Tester/Charger will begin the Voltage Retention Test.
- Unacceptable – The battery will be charged further, maximum charging time period during
‘Optimize’ mode will not exceed half the time the battery was in ‘Normal Charge’ mode.
Continued...

CLASS 4

[Name] – [Title]
LOTUS
CARS LIMITED
*Note: A pre-qualification test Pass = Indicator light #6 constantly illuminated.
PassLOTUS
Fail CARS LIMITED
T +44
(0)1953
[######]
(0)[####
######]
T +44 (0)1953
[######]M +44
M +44
(0)[####
######]
Time period: 2 - 6 hours (cumulative)
[name]@lotuscars.com
[name]@lotuscars.com

CARS

Bulletin number 2019/03
continued Page 3

Time period: up to 30 hours (cumulative)
With the Tester/Charger still connected, charging ceases for 12 hours to determine
Stage 5.
the if battery can retain the charge. At the beginning of this test the green TEST InVoltage
dicator light #6 will flash. Note: During this test, a small load is applied to the cells
Retention
to remove surface charge and improve the accuracy of the test results.
Test
[Text
here].
[Text
here].
- For batteries in good condition, the green TEST Indicator light #6 will continue to flash for

[Next
para
spacing]
[Next
para
thespacing]
full duration of the test and once completed, the maintenance Indicator lights #6, 7
or 8 will remain constantly illuminated to show that the battery is now in the 'Maintenance

Yours
sincerely
/ Kind
regards,
as as
appropriate)
Charge
stage. (Delete
Yours
sincerely
/Cycle'
Kind
regards,
(Delete
appropriate)

- If the voltage decreases below 12.8V within the 30 minutes of beginning the test, then the
test will be suspended and the red TEST Indicator light #8 will flash indicating the battery
may be permanently damaged.

NOTE: Even once charged, if the LED on the top of the voltage protection device IS NOT illuminated,
then this indicates that the voltage protection device requires manually resetting because it is still isolating the battery from the vehicles electrical system.
The charging stages shown in this bulletin are revised extracts taken from the manufacturers’ (Optimate) Tester/Charger instruction manual which are also supplied with any vehicle originally fitted with a
lithium battery, an manufacturers instruction manual is also available on-line.
IMPORTANT POINTS TO CONSIDER
- The battery is only going through a 'Maintenance Charge Cycle' when LED status indicator #6 light
is constantly illuminated.
- The battery is only going through a 'Charge Cycle' when LED 'Charge' indicator #4 light is illuminated.
-- If the battery fails the initial stage 1 'Pre-Qualification Test' it may take up to 30 hours to
fully recharge the battery to an acceptable state before a 'Maintenance Charge Cycle' can be
applied.
-- The lithium battery of any vehicle (new or otherwise) which is being stored within the dealership for any length of time, should be connected to the tester/charger to maintain satisfactory
battery performance.
-- A lithium battery that becomes too deeply discharged the only solution will be to replace it,
which may not be covered under the terms of the vehicle warranty.
Warranty Pre-Authorisation requests should not be submitted until the battery has been subjected to the complete testing/charge cycle as described in this bulletin, the results of readings
taken and charging duration times may also be requested from the Warranty Department before
authorisation for replacement under warranty is considered.
CHARGES:
No warranty charges are associated with the contents of this bulletin.
Ends.

CLASS 4

[Name]
– [Title]
[Name]
– [Title]
LOTUS
CARS
LIMITED
LOTUS
CARS
LIMITED
For batteries in good condition Indicator light #6 will remain constantly illuStage
6.
T +44
(0)1953
[######]
M +44
(0)[####
######]
T +44 (0)1953 [######]
M +44
(0)[####
######]
Maintenance
Charge minated with the battery being maintenance charged until the Tester/Charger
[name]@lotuscars.com
[name]@lotuscars.com
is disconnected.