Constructing an electric scooter battery

Tõuksimaailm offers the service of manufacturing lithium-ion (Li-Ion) batteries for electric scooters, electric bikes or other electric devices, Li-Ion assembling / assembling batteries from 18650 or 21700 format modules. Our aim is to provide Li-Ion batteries of a very high quality and safety level, with parameters and lifetime that are far superior to the standard battery pack that comes with the device. We have experience in building batteries for light electric vehicles since 2020, 10 years of experience in electrical engineering, and have developed a strict quality policy for battery assembly and post-assembly testing. As a standard solution, Tõuksimaailm offers 196 different custom-made Li-Ion battery versions in the voltage range 29.4V – 84V, available for order online. The technical parameters of all standard batteries are shown in a table at the bottom of this page.

Quality policy

The lithium-ion battery of a light electric motorcycle or other electrical equipment is the energy source for this equipment. By way of illustration, Li-Ion batteries contain more energy when fully charged than the same amount of dynamite. This is why lithium-ion batteries can be dangerous in the event of an accident, and will generally destroy the equipment using the battery, damage the external environment of the equipment and sometimes cause major fires. You can read more about the dangers of lithium-ion batteries in our blog post.

When ordering a battery as a special order, it is important to make sure that the battery you are ordering is of high quality and safe to use before placing your order. It is also important that the battery meets the required electrical parameters and is resistant to mechanical shock and vibration. The most important quality and safety factors for a battery are listed below.

Battery module manufacturer brand

A high quality battery is made up of elements (modules) produced by a world-renowned brand. Reputable manufacturers cannot afford the reputational damage caused by poor quality production, which is why strict quality control is ensured in the manufacturing processes. A quality label is when the battery is made from LG, Samsung, Panasonic, Sony, Molicel, EVE, Tesla or Sanyo elements. If the brand of the battery modules is hidden or not stated in the description, it is likely that the battery is not made of high quality elements and it is safer not to buy such a battery. At Tõuksimaailm, we use LG, Samsung and EVE brand battery modules to manufacture our batteries.

Battery module cooling and isolation

Making a safe battery requires that the battery modules are sufficiently cooled and do not overheat (the battery pack does not catch fire) under heavy load. Therefore, building any high quality and safe battery requires the modules to be separated from each other. To achieve this, special battery holders are used which leave space between the battery pack modules for air to circulate – the elements do not overheat and release heat into the air, rather than directly into the adjacent elements. The battery module holders are also slightly flexible (resilient), which helps to absorb shock and vibration to the battery very effectively. Therefore, it is very important that the battery you order uses cell holders, because if cell holders are not used, the modules may not only overheat, but may also over time wear through each other’s shells due to vibration and cause short-circuit.

Be sure to stay away from battery packs that have been glued together with hot glue to reduce the size of the battery or to keep the holders together. Also, by installing a Kapton tape in the module’s edges, there are not enough safe cooling gaps between the modules and the battery may still overheat under heavy load. At Tõuksimaailm, we use 18650 or 21700 cell format battery holders for all our battery builds.

Electrical conductor cross-sections and connections

Building a high quality and durable battery requires that all the conductors used in the assembly of the battery pack are of sufficient cross-section (thickness) to prevent overheating of the conductive parts, all kinds of bad connections (cold junction) and broken connections. The safety battery packs are connected to each other by means of nickel strips of suitable cross-section, spot-welded to the modules. It is advisable to avoid batteries where the modules are connected to each other with copper wires and soldered together, as soldering can cause heat damage to the battery cells and make them unsafe to use. High quality batteries use wires of this cross-section and nickel strips (for connecting the elements) as specified in international standards. In addition to the cross-section, the thermal resistance of the conductors is also very important. In Tõuksimaailm, we use conductors with a cross-section that meets the standards and an operating temperature of 200C in the construction of all our battery packs. Professional spot welding allows us to use 0.3mm thick nickel strip sheets and to produce battery packs with very strong spot welds and high resistance to intense vibration.

Over- and undersizing

If the aim is to maximise the safety and reliability of the electrical equipment, the first point of consideration in the product engineer’s practice is always the under-dimensioning of the electrical parameters of the product and the over-dimensioning of safety-enhancing factors. Reliable batteries are designed in such a way that their maximum output current is not equal to the maximum current allowed by the modules, but is limited by the battery control module (BMS). This helps to ensure that at no point (even for short periods) is any battery element overloaded and the battery life is maximised. Also, safe batteries are built using electrical conductors with a one-step larger cross-section (for example, a thicker 10AWG wire instead of the standard 12AWG wire). In Tõuksimaailm, we use BMSs to limit the current flow of the batteries we manufacture, which are one-third (33%) less than the output current allowed by the modules. We also use the principle of selecting a cross-section one step larger for all conductors.

Battery balancing and fuses

A prerequisite for a battery to be acceptable for any use is that it is protected against short-circuiting by a fast-acting (fusible) fuse, which is usually integrated into the battery BMS. It is also good practice for the battery control board/control module BMS to have integrated protection against battery overcharge (overvoltage protection), undercharge and continuous BMS overload. In addition to these features, the ability of the battery BMS to balance the output voltage of the battery modules is a prerequisite for a long battery life. If the BMS is not capable of balancing the elements, the battery life will generally not exceed a few dozen charging cycles. This is because the internal resistance of all battery modules is slightly different and they discharge slightly differently under load. Thus, a battery without balancing capability is a rather unreasonable device and should be avoided. Tõuksimaailm uses high quality Daly BMSs, which are equipped with all the battery protection features listed above, and are capable of balancing battery cells with currents up to 35mA.

Battery protection from the outside environment

When it comes to the battery of an electric scooter or bicycle, moped or any other electric light cycle/vehicle, the protection of the battery from the external environment is also critical. External environmental effects include the vibrations and shocks already listed above. External influences also include water and other liquids, shocks and pressure/pressure on the battery. A good quality battery is protected from these factors by a strong external casing, sealed with a waterproof sealant. Batteries with only a thermistor or tape installed to protect against external factors should be avoided. In manufactoring of battery shells / housings, we use a glass fibre reinforced plastic material with insulating properties and good thermal conductivity, specially designed for batteries, which we in turn cover with a waterproof thermal barrier and seal with a sealant.

Standard batteries

In order to make it as easy as possible for you to order custom-made Li-ion batteries, we have compiled a list of the most commonly used battery sizes and parameters, which you can order from our online shop without asking for a quote. If you have an electric scooter or an electric bicycle, it is very likely that you will find the right battery for you among our standard batteries.

We offer standard batteries in a wide range of configurations, from 7s2p to 20s12p. The letter “s” indicates the number of elements in the series and the letter “p” indicates the number of elements in parallel. For example, 7s2p means that there are 7 modules connected in a series (7×4.2V=29.4V) and 2 modules in each parallel for a total of 7×2=14 modules.

For each configuration we offer four different types, all composed of elements with different characteristics. The aim is to offer the same configuration of battery packs with different characteristics – maximum capacitance, output current, or price/capacitance ratio. In this way, it is easier to choose the configuration that best suits your needs. Three configurations are made up of 18650 cells and one configuration is made up of 21700 cells. The configuration number is given last in the product code, for example 20S5P4 in the product code means that the configuration number is 4. Configuration numbers mean:

  1. High capacity (18650 modules)
  2. High maximum output current
  3. High price/capacity ratio
  4. High capacity (21700 modules)

Standard batteries can be ordered from the services section of our e-shop:

Batteries of different sizes, different parameters and extra batteries

If you can’t find the right battery pack for you from our range of standard batteries, we can build a custom battery pack for you. If you lack capacity, load current or voltage, we can also build a battery to your specific specification. If you wish to fit an additional battery to your electric vehicle, in addition to the existing battery, we can also provide this service.

In addition, we can build you a new battery inside an old battery casing, build a battery inside a self-made casing, a square or triangular battery. For a quotation for a special solution, please send an e-mail to info@touksimaailm.ee. Price list for special solutions:

  • Quotation for building a special sized battery – 29.50€ (if you order the battery from us, you will get a retroactive discount on the price of the battery by the price of the quotation).

  • Installation and connection of an additional battery to an electric scooter or electric bicycle – 59€ (to be added to the battery installation price).

  • All the elements of the battery are mounted parallel and aligned in the battery, but the elements are positioned non-standardly and the battery does not form a square or rectangle – 29.5€ (to be added to the price of building the battery).

  • Battery consists of several elements assembled in a non-aligned block – 59€ (to be added to the price of building the battery).

  • Aku elementide vahetus olemasoleva aku konstruktsiooni sees – 59€/h

Battery warranty conditions

The quality of our batteries is backed up by our long warranty period. All batteries built in Tõuksimaailm are covered by a 2-year warranty, which is 4 times longer than the average electric scooter battery. The warranty covers all faults not listed below.

Not covered by warranty:

  • Battery failures caused by contact with water or other liquids.
  • Physical damage to the battery (external casing) and battery failures caused indirectly or directly by such damage.
  • Battery BMS malfunctions when a short-circuit is generated at the battery output
  • Failures caused by storing the battery in the wrong conditions or charging the battery incorrectly – you can read about charging the battery correctly in our blog post.

Price list for standard size batteries

To see the battery price, click on the green “+” circle in front of the row.

TootekoodKonfiguratsioon (s/p)Nominaalpinge (V)Maksimaalne pinge (V)Mahtuvus (Ah)Mahtuvus (Wh)Maksimaalne koormus (A)Maksimaalne laadimisvool (A)Pikkus (mm)Laius (mm)Kõrgus (mm)Hind (€) koos km
7S2P17s2p2429.46.8163.2156.81467253214.55
7S2P27s2p2429.451203081427256198.31
7S2P37s2p2429.45120152.51467253168.91
7S2P47s2p2429.49.78234.72203.261777661218.47
7S3P17s3p2429.410.2244.820101467276292.33
7S3P27s3p2429.47.518040121467276267.97
7S3P37s3p2429.47.5180153.751467273223.87
7S3P47s3p2429.414.67280.08304.891777684298.21
7S4P17s4p2429.413.6326.43013.61467296370.11
7S4P27s4p2429.410240501614672100337.63
7S4P37s4p2429.4102402051467296278.83
7S4P47s4p2429.419.56469.44406.5217776106377.95
10S2P110s2p36426.8244.8156.82067253281.22
10S2P210s2p364251803082067256258.02
10S2P310s2p36425180152.52067253216.02
10S2P410s2p36429.78352.08203.262467661286.82
10S3P110s3p364210.2367.22010.22067276392.33
10S3P210s3p36427.527040122067276357.53
10S3P310s3p36427.5270153.752067273294.53
10S3P410s3p364214.67420.12304.892467684400.73
10S4P110s4p364213.6489.63013.62067296503.44
10S4P210s4p364210360501620672100457.04
10S4P310s4p3642103602052067296373.04
10S4P410s4p364219.56704.16406.5224676106514.64
10S5P110s5p364217612301520672116614.55
10S5P210s5p364212.5450602020672120556.55
10S5P310s5p364212.5450306.2520672116451.55
10S5P410s5p364224.45880.2508.1524676133628.55
10S6P110s6p364220.4734.4402020672136725.66
10S6P210s6p364215540802420672143656.06
10S6P310s6p364215540307.520672136530.06
10S6P410s6p364229.341056.24609.7824676155742.46
10S7P110s7p364223.8856.85023.820672160836.77
10S7P210s7p364217.56301002820672168755.57
10S7P310s7p364217.5630408.7520672160608.57
10S7P410s7p364234.231232.286011.4124676178856.37
13S2P113s2p4854.66.8326.4156.82667253347.89
13S2P213s2p4854.652403082667256317.73
13S2P313s2p4854.65240152.52667253263.13
13S2P413s2p4854.69.78469.44203.263157661355.17
13S3P113s3p4854.610.2489.620102667276492.33
13S3P213s3p4854.67.536040122667276447.09
13S3P313s3p4854.67.5360153.752667273365.19
13S3P413s3p4854.614.67704.16304.893157684503.25
13S4P113s4p4854.613.6652.83013.62667296636.77
13S4P213s4p4854.610480501626672100576.45
13S4P313s4p4854.6104802052667296467.25
13S4P413s4p4854.619.56938.88406.5231576106651.33
13S5P113s5p4854.617816301526672116781.21
13S5P213s5p4854.612.5600602026672120705.81
13S5P313s5p4854.612.5600306.2526672116569.31
13S5P413s5p4854.624.451173.6508.1531576133799.41
13S6P113s6p4854.620.4979.2402026672136925.66
13S6P213s6p4854.615720802426672143835.18
13S6P313s6p4854.615720307.526672136671.38
13S6P413s6p4854.629.341408.32609.7831576155947.5
13S7P113s7p4854.623.81142.45023.8266721601070.1
13S7P213s7p4854.617.58401002826672168964.54
13S7P313s7p4854.617.5840408.7526672160773.44
13S7P413s7p4854.634.231643.046011.41315761781095.58
13S8P113s8p4854.627.21305.65025266721801214.54
13S8P213s8p4854.62096010032266721881093.9
13S8P313s8p4854.620960401026672180875.5
13S8P413s8p4854.639.121877.768013.04315762031243.66
13S9P113s9p4854.630.61468.86030266722001358.98
13S9P213s9p4854.622.5108012036266921841223.26
13S9P313s9p4854.622.510805011.2526672200977.56
13S9P413s9p4854.644.012112.488014.67315762261391.74
13S10P113s10p4854.63416326030266722201503.43
13S10P213s10p4854.625120012040266922041352.63
13S10P313s10p4854.62512005012.5266722201079.63
13S10P413s10p4854.648.92347.210016.3315762481539.83
14S2P114s2p5258.86.8353.6156.82867253370.11
14S2P214s2p5258.852603082867256337.63
14S2P314s2p5258.85260152.52867253278.83
14S2P414s2p5258.89.78508.56203.263387661377.95
14S3P114s3p5258.810.2530.420102867276525.66
14S3P214s3p5258.87.539040122867276476.94
14S3P314s3p5258.87.5390153.752867273388.74
14S3P414s3p5258.814.67606.84304.893387684537.42
14S4P114s4p5258.813.6707.23013.62867296681.21
14S4P214s4p5258.810520501628672100616.25
14S4P314s4p5258.8105202052867296498.65
14S4P414s4p5258.819.561017.12406.5233876106696.89
14S5P114s5p5258.817884301528672116836.77
14S5P214s5p5258.812.5650602028672120755.57
14S5P314s5p5258.812.5650306.2528672116608.57
14S5P414s5p5258.824.451271.4508.1533876133856.37
14S6P114s6p5258.820.41060.8402028672136992.32
14S6P214s6p5258.815780802428672143894.88
14S6P314s6p5258.815780307.528672136718.48
14S6P414s6p5258.829.341525.68609.78338761551015.84
14S7P114s7p5258.823.81237.65023.8286721601147.87
14S7P214s7p5258.817.591010028286721681034.19
14S7P314s7p5258.817.5910408.7528672160828.39
14S7P414s7p5258.834.231779.966011.41338761781175.31
14S8P114s8p5258.827.21414.45025286721801303.43
14S8P214s8p5258.820104010032286721881173.51
14S8P314s8p5258.8201040401028672180938.31
14S8P414s8p5258.839.122034.248013.04338762031334.79
14S9P114s9p5258.830.61591.26030286722001458.98
14S9P214s9p5258.822.5117012036286921841312.82
14S9P314s9p5258.822.511705011.25286722001048.22
14S9P414s9p5258.844.012288.528014.67338762261494.26
14S10P114s10p5258.83417686030286722201614.53
14S10P214s10p5258.825130012040286922041452.13
14S10P314s10p5258.82513005012.5286722201158.13
14S10P414s10p5258.848.92542.810016.3338762481653.73
16S2P116s2p6067.26.8408156.83267253414.55
16S2P216s2p6067.253003083267256377.43
16S2P316s2p6067.25300152.53267253310.23
16S2P416s2p6067.29.78586.8203.263847661423.51
16S3P116s3p6067.210.261220103267276592.33
16S3P216s3p6067.27.545040123267276536.65
16S3P316s3p6067.27.5450153.753267273435.85
16S3P416s3p6067.214.67700.2304.893847684605.77
16S4P116s4p6067.213.68163013.63267296770.1
16S4P216s4p6067.210600501632672100695.86
16S4P316s4p6067.2106002053267296561.46
16S4P416s4p6067.219.561173.6406.5238476106788.02
16S5P116s5p6067.2171020301532672116947.88
16S5P216s5p6067.212.5750602032672120855.08
16S5P316s5p6067.212.5750306.2532672116687.08
16S5P416s5p6067.224.451467508.1538476133970.28
16S6P116s6p6067.220.412244020326721361125.65
16S6P216s6p6067.2159008024326721431014.29
16S6P316s6p6067.215900307.532672136812.69
16S6P416s6p6067.229.341760.4609.78384761551152.53
16S7P116s7p6067.223.814285023.8326721601303.43
16S7P216s7p6067.217.5105010028326721681173.51
16S7P316s7p6067.217.51050408.7532672160938.31
16S7P416s7p6067.234.232053.86011.41384761781334.79
16S8P116s8p6067.227.216325025326721801481.2
16S8P216s8p6067.220120010032326721881332.72
16S8P316s8p6067.22012004010326721801063.92
16S8P416s8p6067.239.122347.28013.04384762031517.04
16S9P116s9p6067.230.618366030326722001658.98
16S9P216s9p6067.222.5135012036326921841491.94
16S9P316s9p6067.222.513505011.25326722001189.54
16S9P416s9p6067.244.012640.68014.67384762261699.3
16S10P116s10p6067.23420406030326722201836.75
16S10P216s10p6067.225150012040326922041651.15
16S10P316s10p6067.22515005012.5326722201315.15
16S10P416s10p6067.248.9293410016.3384762481881.55
16S11P116s11p6067.237.422448037.4326722432014.53
16S11P216s11p6067.227.5165015044326922241810.37
16S11P316s11p6067.227.516506013.75326722401440.77
16S11P416s11p6067.253.793227.410017.93384762762063.81
16S12P116s12p6067.240.824488040326722632192.3
16S12P216s12p6067.230180015048326922441969.58
16S12P316s12p6067.23018006015326722601566.38
16S12P416s12p6067.258.683520.812019.56384962742246.06
20S2P120x2p72846.8489.6156.84067253503.44
20S2P220x2p728453603084067256457.04
20S2P320x2p72845360152.54067253373.04
20S2P420x2p72849.78704.16203.264767661514.64
20S3P120s3p728410.2734.420104067276725.66
20S3P220s3p72847.554040124067276656.06
20S3P320s3p72847.5540153.754067273530.06
20S3P420s3p728414.67840.24304.894767684742.46
20S4P120s4p728413.6979.23013.64067296947.88
20S4P220s4p728410720501640672100855.08
20S4P320s4p7284107202054067296687.08
20S4P420s4p728419.561408.32406.5247676106970.28
20S5P120s5p72841712243015406721161170.1
20S5P220s5p728412.59006020406721201054.1
20S5P320s5p728412.5900306.2540672116844.1
20S5P420s5p728424.451760.4508.15476761331198.1
20S6P120s6p728420.41468.84020406721361392.32
20S6P220s6p72841510808024406721431253.12
20S6P320s6p7284151080307.5406721361001.12
20S6P420s6p728429.342112.48609.78476761551425.92
20S7P120s7p728423.81713.65023.8406721601614.53
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20S7P420s7p728434.232464.566011.41476761781653.73
20S8P120s8p728427.21958.45025406721801836.75
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20S8P420s8p728439.122816.648013.04476762031881.55
20S9P120s9p728430.62203.26030406722002058.97
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20S9P320s9p728422.516205011.25406722001472.17
20S9P420s9p728444.013168.728014.67476762262109.37
20S10P120s10p72843424486030406722202281.19
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20S10P320s10p72842518005012.5406722201629.19
20S10P420s10p728448.93520.810016.3476762482337.19
20S11P120s11p728437.42692.88037.4406722432503.41
20S11P220s11p728427.5198015044406922242248.21
20S11P320s11p728427.519806013.75406722401786.21
20S11P420s11p728453.793872.8810017.93476762762565.01
20S12P120s12p728440.82937.68040406722632725.63
20S12P220s12p728430216015048406922442447.23
20S12P320s12p72843021606015406722601943.23
20S12P420s12p728458.684224.9612019.56476962742792.83